COLUMBIA, Mo. -- Drew Lock arrived at Missouri two years ago with a powerful right arm, fluffy bangs and an easy confidence. He seemed ready to be a Southeastern Conference quarterback.

A few months later, after he was hustled into the starting lineup by necessity and became a tackling dummy for SEC opponents, his father was concerned.

"I specifically remember watching him walk out the locker room after the Florida game and worrying about him as he walked toward me," said Andy Lock, a former offensive lineman at Missouri. "He was limping, head down, shoulders dropped. I thought, 'Boy, that's not my son right there.'"

College football hasn't been as easy as it first looked for Drew Lock, but as he enters his junior year, he is positioned for a breakout season. The Tigers return 10 offensive starters and have a year of experience in offensive coordinator Josh Heupel's system.

"It's starting to feel like high school again," said Lock, who starred in football and basketball at Lee's Summit High School in suburban Kansas City. "I'm just going out and having fun. I'm not worried about remembering this or remembering that or adjusting to defenses. It's just kind of flowing. The game is slowing down."

Lock took over as the starting quarterback in the fifth game of the 2015 season after Maty Mauk was suspended. However, he couldn't ignite a troubled offense that failed to score in double figures in six of its 12 games. Coach Gary Pinkel announced his retirement after the 5-7 season. His replacement, Barry Odom, introduced a different system coordinated by Heupel.

As a sophomore, Lock put up good numbers -- 3,399 passing yards with 23 touchdowns and 10 interceptions -- but in an offense predicated on a blistering pace, he sometimes felt mentally a step behind. Missouri suffered its second straight losing season, finishing 4-8. It wasn't until this offseason, Lock said, that he fully grasped the system.


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"He's come a long ways," Heupel said. "Because of that, you're a much calmer player, more confident, you're in control. When you're playing fast, he's still within himself. And he understands when he wants to slow it down and make sure everything is right."

Last year, to keep a new offense simple, Heupel often asked Lock to read one predetermined side of the field and stick with whatever play was called. This season, Lock said he'll be making full-field reads more often and has the freedom to call audibles.

"That's part of being able to trust that he's going to make the right read and repping it enough to know he's going to," Odom said. "We are putting a lot on his plate. So far, so good."

There is no questioning Lock's arm strength. He can make all the throws required at this level and the next. At 6-foot-4 and 225 pounds, he has prototypical size for an NFL quarterback. Accuracy has been the issue. He has completed only 52.5 percent of his passes for his career, and his goal is to complete 65 percent of his passes this season.

That will require some cooperation from a receiving corps that was prone to drops last year. The Tigers should have plenty of weapons with their top four wideouts returning -- including J'Mon Moore, who had 1,012 receiving yards last year -- and a potential star at tight end in Kendall Blanton, an athletic 6-6, 260-pound sophomore.

With that supporting cast and a firm grasp of the offense, Lock has a renewed air of confidence that he can be one of the best quarterbacks in the SEC.

"I've seen a rebirth of Drew Lock," his father said.