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The Oakland Raiders are displaying that they plan to be a factor in the AFC West.

The San Diego Chargers can't say the same because of a penchant for blowing fourth-quarter leads.

San Diego (1-3) has blown three leads in the game's final five minutes and aims to halt a nine-game division losing streak when it visits the Raiders on Sunday (4:25 p.m., CBS).

While the Chargers couldn't figure out how to protect another lead, Oakland (3-1) rallied for a road victory in Baltimore last Sunday, revealing the clutch gene that San Diego seems to lack.

Raiders quarterback Derek Carr tossed a 23-yard touchdown pass to receiver Michael Crabtree with 2:12 remaining to provide Oakland with a 28-27 victory. Coach Jack Del Rio sees the comeback as another sign of the progression of Carr, who threw four touchdown passes in the win.

"He is a guy that is very well-prepared," Del Rio said. "He's really, I think, taken a step forward in terms of emotional control, the poise to be, kind of, surgeon-like and just be accurate with the ball and let his playmakers do their thing.

"So, it's a combination of things but I think he's definitely taken a step forward for us."

Meanwhile, San Diego is heading backwards as it can't close out games under beleaguered coach Mike McCoy.

The Chargers blew a 13-point lead while losing to New Orleans 35-34 last Sunday. Running back Melvin Gordon and receiver Travis Benjamin each lost fourth-quarter fumbles to set the stage for the team's latest collapse.

San Diego also let fourth-quarter leads get away in losses to Kansas City and Indianapolis.

"There's 53 minutes of some good football and then unfortunately we turned the ball over twice there to give them a great opportunity to do what they did," McCoy said of the Saints' game. "You're furious when you watch because you see all the positives, but then there's the blowups.

"We can put it on two plays, but that's not the only reason. There's a number of times during the games. Like I told the players, that's every week. There's so many things we can do better."

The setbacks have increased speculation that McCoy's job is in jeopardy, but the fourth-year coach said he isn't worried about being dismissed.

San Diego's injury-riddled roster took another hit Wednesday, when Pro Bowl cornerback Jason Verrett said he would miss the rest of the season with a partially torn ACL in his left knee.

"The feeling I had in my knee, I knew something wasn't right but I have the mindset of being out there," Verrett said. "Then getting the results, it was crushing. It was tough, but I knew something wasn't right."

The loss of Verrett and the probable absence of veteran cornerback Brandon Flowers (concussion) will make it harder for the Chargers to halt the Oakland passing game.

Carr has passed for 1,066 yards, nine touchdowns and one interception. Crabtree, who has 26 catches for 308 yards, had a career-best three touchdowns against the Ravens and is tied for the NFL lead with four scoring receptions.

"He was so committed to making sure he made so many plays for me that I would always look his way -- that's what he wants and so far, he's done that," Carr said. "You have to give him credit. The guy's worked his tail off and he's super competitive to get to where he's at to where if it's one-on-one, he's a great matchup."

The Raiders have struggled on the defensive side and are allowing a league-worst 460.0 yards per game. Standout defensive end Khalil Mack finally recorded his first sack of the season against Baltimore after posting 15 last season.

San Diego quarterback Philip Rivers has passed for 1,110 yards, seven touchdowns and one interception despite losing standout receiver Keenan Allen (knee) for the season. Gordon leads the NFL with six rushing touchdowns after not finding the end zone as a rookie, but he is averaging a paltry 3.2 yards per carry.

First-round pick Joey Bosa, the defensive end from Ohio State, is expected to make his NFL debut for the Chargers.

San Diego's most-recent win over an AFC West foe came against the Raiders 13-6 on Nov. 16, 2014. The Chargers lost their final two division games that season, went 0-6 versus the AFC West last season, and lost to Kansas City in this season's opener.

The Raiders averaged 30 points while sweeping last season's two meetings.