There have been injuries and fumbles, not to mention the high expectations of following a running back with Hall of Fame credentials.
The first three years of Ryan Mathews' NFL career haven't gone the way he or San Diego Chargers fans thought they would after he was deemed the heir apparent to LaDainian Tomlinson.
OK, so Mathews did make the Pro Bowl two seasons ago.
But then came last year's nightmare. He broke his right collarbone on his first carry of the exhibition season, committed a crucial fumble that got his number of carries reduced and then broke his left collarbone in December.
Mathews is healthy and less bulky this season, and vowing to have more fun under new coach Mike McCoy, who has promised a fresh start for everyone.
"My career kind of begins now," Mathews said.
"Football's always been fun but I think I put too much pressure on myself the last few years trying to be someone I'm not," Mathews said. "It's a tough act to follow when you're following someone like L.T. and I think that's where I got my mindset, that I had to be him, I had to do everything he was doing. I had to score 28 touchdowns in a year and I had to rush for 2,000 yards."
After Tomlinson was released following the 2009 season, the Chargers moved up 16 spots in the draft to take Mathews with the 12th pick overall.
Mathews had idolized Tomlinson to the point that he wore No. 21 while at Fresno State.
Mathews knew there would be comparisons and expectations, but he did understand the distinction that he was following Tomlinson, the NFL's MVP in 2006, not trying to replace him.
Mathews seems to have stood out for things other than hitting the hole and making big gains.
As a rookie, he sustained a high ankle sprain and developed fumbleitis. He struggled so badly at picking up blitzes that then-coach Norv Turner held him out of one game even though he was healthy.
At the open of camp in 2011, after the NFL lockout ended, Mathews struggled to keep pace with his fellow skill players in a surprise conditioning test.
Early in camp last year, he was banged up when he lost control of his BMW while driving from his home to the team hotel.
Then came the collarbone injuries and fumbles.
He ended the season on injured reserve after running for 707 yards and just one touchdown.
Two defensive players had more touchdowns that Mathews.
Mathews' three-year totals are 2,476 yards rushing and 14 touchdowns. By comparison, Tomlinson had 4,564 yards and 37 touchdowns through his first three seasons.
"I got away from just playing football and just having fun and being me," Mathews said. "In college I didn't think about getting drafted until like two days before I declared for the draft. I was just out there having fun and just being with my teammates. That's what I want to do this year."
McCoy knows what went on in the past but is more interested in what happens starting on opening night against the Texans on Sept. 9.
"He's going to be a key player for us. We're going to re-instill the confidence in him and get him going," McCoy said.
McCoy plans to rotate backs, find out which plays suit each back, how they do in the passing game and how they can help protect quarterback Philip Rivers.
"He's just got to get back to doing what he does and hey, trust the line," McCoy said. "Run the ball the way it's supposed to be blocked. And it's the line's job to do a better job of blocking the run game, also.
"Everyone's starting with a clean slate. Some were better than others in how they felt after last year, but we're moving on from last year and he's going to have a great year this year."
Mathews said he hit the weights hard last year because he thought he needed to be bulkier to better take the pounding. Realizing that cost him flexibility, he's slimmed down.
Rivers called Mathews' collarbone injuries "unfortunate."
"What are you going to do? You can't suck it up and go play without a collarbone," Rivers said. "He's had a tough go at it from an injury standpoint. But I think you saw in the year previous when he was able to stay healthy for an extended period of time, he got in a rhythm and got on a roll. You've got to get in the flow. A running back touching it two, three, four times a game, missing four games, it's hard to get in a rhythm."
Mathews' best season was 2011, when he had 1,071 yards and went to the Pro Bowl.
Mathews seems more relaxed than in previous years. On the first day of training camp, he did several interviews.
"It all comes with the territory," he said. "You've got to take everything that comes at you and have fun with it. In the past, I didn't like doing interviews. It was all that pressure, pressure, pressure. I'm going to have fun with it and just go back to my normal self.
"I still expect to do great things," he said. "I need to get back to the basics."
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