NASHVILLE, Tenn. (AP) In one sense, Matt Cassel's football career is right back where it started - even before he entered the NFL.
Cassel signed a one-year deal in the offseason to back up Tennessee Titans quarterback Marcus Mariota, the 2014 Heisman Trophy winner from Oregon.
A dozen years earlier, while in college at Southern California, Cassel had an up-close view of another Heisman Trophy winner. Cassel backed up USC star Matt Leinart, who won college football's highest individual honor in 2004.
In between, Cassel has carved out a nice career of his own, one that has included six NFL stops and has ranged from filling in for Tom Brady to earning a Pro Bowl berth for the Kansas City Chiefs in 2010 with a little of everything in between.
At age 34, Cassel knows his role now is to mentor Mariota and be ready to be called upon just in case.
The Titans made the decision to go with Cassel, and a few weeks after signing him moved on from last year's primary backup Zach Mettenberger, who was waived and claimed by the San Diego Chargers.
Not only is the Titans organization what Cassel was seeking after splitting last season between Buffalo and Dallas, but the Nashville area was a fit as well.
''It was a great fit for me. I think not only from an organizational standpoint, but from a place to live,'' Cassel said.
''I also understand my role. Obviously, we've got a very young, talented quarterback ahead of me. I was in a program when I was young where my elder was Tom and I was able to learn a lot, and I understand that my role is to come in and help him develop and be the best he can be.
''Anything I can do to help him along the way is something that will be valuable to the team and help us win games hopefully.''
Mariota started 12 games as a rookie last season and threw for 2,818 yards and 19 touchdown passes. Cassel admired Mariota's play from afar and now appreciates it even more up close.
''In my mind, for a young guy to come in and play the way he did last year, and then also actually sit here and evaluate him this offseason, I've been impressed with each and every facet of his game,'' Cassel said.
''He's very smart. He's talented and he can make all the throws, but he's also got an unbelievable ability to make people miss and run.
''The sky's the limit for him. He's just got to continue to work, and I don't think that's an issue for him. He's one of the first guys in the building every day. I've got nothing but respect for him, and I love working with him.''
The feeling is mutual in terms of what Mariota takes from watching and listening to the veteran in practice and the meeting room.
''He's been incredible for me, and (third-stringer) Alex Tanney has too. To have the quarterback room the way it is now, for me, it's been really helpful,'' Mariota said. ''After every single set, I can talk to one of those guys and ask them what they saw.''
Cassel has been on good, bad and even great teams at times in his career. Although the Titans have won just five games combined over the past two seasons, Cassel is optimistic.
''I think we're headed in the right direction,'' Cassel said. ''I know one thing, this team is a team that likes to work. We're young, but at the same time, these guys all give great effort.
''We had a great offseason. Now it's about coming together in camp and pushing each other and understanding the system and what the coaching are trying to accomplish on each and every play and growing as a team.''
NOTES: The Titans have waived cornerback Bennett Okotcha, who had a shoulder injury. Okotcha joined the team May 16 as an undrafted free agent from Texas-San Antonio. ... Titans coach Mike Mularkey said Tuesday that wide receiver Kendall Wright ''tweaked his hamstring'' in practice.
AP NFL website: www.pro32.ap.org and www.twitter.com/AP-NFL