NAPA, Calif. (AP) — Derek Carr's career has been on an upward trajectory ever since entering the NFL as a second-round pick three years ago.

Ten straight losses to open an up-and-down rookie season in 2014 was followed by a much-improved sophomore campaign that still fell short of the postseason.

Carr then emerged as one of the better passers in the league last season when he led the Raiders to 12 wins and a playoff berth for the first time since 2002 and was talked about as an MVP candidate.

Now Carr enters year four as the player with the richest contract in the league after signing a $125 million, five-year extension this offseason and an expectation that his best football is still ahead of him.

"I hope so," Carr said. "I don't put measurements on it like stats and things, but from a decision-making standpoint, from a poised and comfort standpoint, playing the game with more knowledge, more wisdom, from that standpoint I hope I grow every single year. I really do. I hope I get better every year. ... There's always room to improve and I'm going to work to try to improve that."

If Carr manages to improve on last season that would buck history. He became the 13th quarterback in the past 30 years to start at least 10 games in his first season and have his passer rating improve in each of the next two seasons.

Only Troy Aikman followed that with another year of improvement in year four, leading the Dallas Cowboys to a Super Bowl title. The other 11 quarterbacks saw their passer rating drop by an average of nearly 10 points in year four, a group that includes quarterbacks such as Peyton Manning and Cam Newton.

"The best thing about Derek, and I mean this sincerely, is that he wants to be great," offensive coordinator Todd Downing said. "He understands that to be great, it's always a learning process. It's always a growing process. ... For him, it's just consistency. It's taking those little details and refining them as much as he possibly can, so that when he has the perfect look, when he has the opportunity to attack a one-on-one, he's as accurate as he can be or get us in and out of the right place and the right situations."

Carr did many great things last season, completing a career-best 63.8 percent of his passes with 28 touchdowns and only six interceptions before a broken leg in the second-to-last game of the regular season cost Oakland a possible division title and led to a first-round playoff exit.

Carr also led seven fourth-quarter comebacks as he played at his best in the biggest moments, finishing tied for third in the MVP voting, but knows there's still plenty of room for improvement.

"Our goal is to make sure that we don't take any steps backward," he said. "That is not talking statistically or anything like that. Those things come. It's just the efficiency of how we run our routes, the efficiency of my footwork, the efficiency of how we pick up the blitzes, all of those things. And if we're getting better in those areas, those other things will fall into place."

One area of improvement could come in how often Carr goes downfield. Despite having one of the NFL's top pass blocking lines with three Pro Bowlers that allowed a league-low 18 sacks last season and one of the strongest arms in the game, he was still one of the more cautious quarterbacks.

Carr ranked in the top 10 in the league with more than one-fifth of his passes were thrown behind the line, according to game charting from the Pre-Snap Reads quarterback catalogue. He was near the bottom in deep throws and his average pass traveled just over 8 yards downfield, ranking 22nd in the league.

Only five quarterbacks got rid of the ball faster than Carr, according to SportRadar, so he possibly missed out on opportunities for bigger plays downfield.

But after watching big brother David get sacked an average of 50 times a year his first five seasons, Derek knows it's a fine line to balance.

"You have to take what they give you because you have to take some pressure off the offensive line, because if you're back there holding onto it and getting hit, that's your fault," he said.

"Get the ball out of your hands, but at the same time when the shot is there, then you take it. But, never where I just try to sit back there all day and force a shot."

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