The San Francisco 49ers host the Arizona Cardinals this weekend and will be without at least one of their playmakers. Rookie wide receiver Dante Pettis has not been a regular big play threat http://www.authenticssanfrancisco49ers.com/cheap-pierre-garcon-jersey , but when he gets the ball in his hands, big things happen. He has already been ruled out with a knee injury, and is week-to-week moving forward.Wide receiver Marquise Goodwin is questionable with a thigh and hamstring issue, and we’ll find out more about his status Wednesday afternoon with the first practice participation report. My guess is Goodwin will be fine, but even if he plays, the team will still be without Pettis.This opens the door for second year receiver Kendrick Bourne. Through four games, Bourne is on pace for 20 receptions and 260 yards, which are not drastic increases from his 11-game rookie season. However, he already has two touchdowns, putting him on pace for eight this season after not reaching the end zone as a rookie.It’s a small sample size, but he is establishing himself as a red zone threat in different ways. His first touchdown, against the Detroit Lions, was primarily a play design that worked perfectly.His second touchdown, against the Los Angeles Chargers, came on a quick slant route in which Bourne got open and C.J. Beathard threw a perfect pass to him. Even though both plays were not 100 percent about Bourne’s work, he executed his role and got the job done. That might earn him more looks moving forward. He had no targets in Week 1, and two total in Weeks 2 and 3. Beathard targeted him three times, which could mean we see more of him in Week 5.The 49ers PR staff released their unofficial depth chart on Wednesday, and the wide receiver position does offer one particular question. The depth chart included Victor Bolden among the wide receivers. He has been reinstated from his four-game PED suspension, but the team has a one-week exemption to get him back on the roster. If Goodwin can’t play, we might see him this week, but if Goodwin can play, I suspect the team waits until next Monday to release a player. They have enough issues elsewhere on the roster that they probably have to go thin at wide receiver this week.49ers offensive depth chart, Week 5 vs. CardinalsPositionFirstSecondThirdPositionFirstSecondThird49ers defensive depth chart, Week 5 vs. CardinalsPositionFirstSecondThirdPositionFirstSecondThird49ers special teams depth chart, Week 5 vs. CardinalsPositionFirstSecondThirdPositionFirstSecondThird49ers young linebackers learn on the fly This past Sunday versus the Los Angeles Chargers we saw glimpses of what the San Francisco 49ers could be defensively. I noticed several adjustments since the Chiefs game that put our defensive talent in better position to be successful. I also saw better performance from our trio of linebackers, Reuben Foster, Fred Warner, and Malcolm Smith. Against the Chiefs, Smith was a disaster, he was slow to the point of attack and often looked out of position. Against the Chargers White Richard Sherman Jersey , he played well at SAM. The combo of Foster and Warner are the focus for this article. We sometimes forget because of their incredible potential and flashes of what we’ve seen that these two players aren’t all-pros. They’re a rookie third round pick, in Warner, and a second year player, in Foster, who missed several games last season, and the first two games this season. The Chargers game plan was to attack these two and take advantage of their limited exposure to the NFL.Foster and Warner run well and they’re exceptionally instinctive. You will see plays every week, where you can see these guys are special. However Ken Whisenhunt, the Chargers OC, and Philip Rivers have seen more plays in their sleep then these two backers. Gus Bradley, the chargers defensive coordinator, runs the same defensive system as San Francisco. To add another layer Robert Saleh, our DC worked directly under Bradley in Seattle. I’m sure he was able to provide some insights into the strengths and weaknesses of this defensive system, and provide some insight into how Saleh thinks and adjusts. Let’s get into the film.Our first clip shows how the Chargers attacked our linebackers all game. They ran people through Warner and Foster’s middle zone and waited to see who would bite. Its hard to say either player reacted poorly, but this play outlines a fundamental flaw in the system. With no pass rush to really push the issue, Rivers had the time to wait for Melvin Gordon to leak out the backfield and make an easy catch and run. As the tape stops, you can see Keenan Allen, has the attention of three 49er defenders. From the end zone angle we can watch Foster and Warner react to the play action. Foster bites hard, he’s almost at the line of scrimmage when Rivers fakes the hand off. Warner doesn’t bite at all, but I believe because of Foster’s over pursuit he turns and starts running with the WR sooner than he probably would have if Foster wasn’t so out of position. This prevents him from even seeing the RB Gordon leaking out of the backfield.Our next clip gives another good example of the Chargers scheme exploiting our defensive zone. I felt like the defense did better in man coverage, whenever we would switch to zone we would give up a big play or solid yards. Man coverage prevents our young players eyes from lying to them. They have limited responsibilities and can really focus on one player. We saw how the shifts and movements affected our defense in the Kansas City game, and we’re seeing the same results here.Before the play starts you can see Foster and Warner kind of switching back and forth trying to get in the right alignment. The two receivers at the bottom of the screen run the same route, but the first receiver Keenan Allen again runs through the zone attracting the attention of multiple defenders. As the play stops three zone defenders are just sort of watching Rivers without really being aware of the receiver running by them. The second receiver Tyrell Williams is left uncovered for a big gain. The end zone angle highlights a great move and rush by Cassius Marsh, sweet inside move just not quick enough to really effect the play. He wins a lot with that inside move, once he develops some more counters he will be effective.Chargers running back Melvin Gordon caught seven passes for 55 yards, averaging 7.9 yards per reception. His success was solely related to our linebackers inexperience with a versatile back like Gordon. This next play shows how the Chargers aligned him in a certain position to attract a certain coverage, only to run him on a route to exploit that initial read. From the high angle, we can see what appears to be a pretty standard swing pass and catch. The end zone angle tells a little more. As the Chargers set up Gordon lines up to the right of Rivers.As the tape stops, we see Foster pointing to Gordon “I got him.” He could just be saying watch him, but I believe he’s calling out his coverage. At the snap, however, Gordon runs behind Rivers into the flat on the opposite side of the field. Foster is sort of stuck Youth Mike Person Jersey , as the play stops again, he’s pointing to Gordon again as he realizes he’s out of position. Warner, by now is also out of position and takes a poor angle in coverage. To further prevent Foster from getting after Gordon in coverage, the Chargers run two slant routes right in front of him. He’s torn between what he saw during the pre snap, and what’s actually happening on the field. This next clip is an identical play we saw the Chiefs pull off several times during last week’s game. Some call it an RPO, it could be a standard play-action pass. Either way it’s made to confuse linebackers in coverage. The running back and offensive line roll right as if the play was a run sweep to the outside. However Rivers pulls the ball out and hits and easy slant to a wide open receiver. Foster and Warner bite hard and leave a huge gap behind them. That’s two teams running the same play against us. I’m not sure if there is really a successful defensive call against this type but, our linebackers being young and aggressive compounded the problem.Despite these breakdowns every so often, we still had a chance to win the game. The Chargers were down two points looking to drive down the field. We’re going to look at three key plays that lead to their game-winning field goal, and what we should be looking for in the upcoming weeks defensively. First key play. It’s the same play as above, Chargers found something that worked and went to it again. Easy 10 yards. Saleh needs to come up with a scheme or coverage to prevent this type of exploitation.Second key play. This reverse was a gutsy call, but still looked to take advantage of our linebackers over pursuing. In so many ways it worked, Warner is totally out of position, Foster gets hooked, even the back side players Antone Exum Jr. and Solomon Thomas nearly run themselves out of the play. However, both of them have a chance at the tackle. I’m usually not one to point to the referees as a reason why a play did or didn’t work, but if this isn’t a blatant block in the back, I don’t know football. What’s worse is that this official is standing right there as this illegal block takes out two 49ers and springs the runner for a long gain. It’s disheartening but we need to work on being sound, and not over pursuing.The third key play somewhat summarizes all that we’ve discussed around our defense. Poor alignment, poor tackling, and poor effort. This long run by Gordon was the “nail in the coffin.” The Chargers kicked a field goal after this play to go up two and win the game. Not a real dynamic play call here, standard running play to the right, alignment wise we’re out flanked from the snap. The Chargers guard does a great job of pushing Deforest Buckner inside, and then getting to the second level on Foster. The end Ronald Blair is lined up inside the offensive tackle and is easily pushed inside. There’s a wide open lane for the pulling guard with Gordon behind him. Once Gordon breaks through Greg Mabin is the first person to wrap him up, but then DJ Reed shows poor form by running up and throwing a shoulder at him and subsequently knocks Mabin off the runner.What I don’t like at all is the jogging on this play, as Gordon breaks the tackle I highlight several 49ers not engaged and loafing. If I was Kyle and Co. I’d show this play over and over again. It’s a key play, we need to get off the field, and these guys are jogging. After the end zone angle I show the high angle for one reason. I’m not trying to dump on Ahkello Witherspoon, but look at this guy jog, even after the broken tackle he’s jogging. I’m not sure what the problem is but this can’t happen. Show some urgency! Go Niners!