Dennis Dixon is learning there are two speeds played in any NFL game: fast and faster. He's also discovering that's the pace at which NFL coaches go in making personnel decisions.
"I'm going to have to (play better)," said Dixon, the No. 3 QB on the depth chart when training camp began. "I've got to improve day in and day out, on a week-to-week basis, while my number is called."
Dixon didn't play badly enough to lose that game, but he didn't play well enough to win many games.
Leftwich was scheduled to start against the Falcons, Titans, Tampa Bay Buccaneers and Baltimore Ravens while Roethlisberger sat out, only to sprain the medial collateral ligament in his left knee during the final preseason game Sept. 2. He could be ready to play as early as Sept. 26 at Tampa Bay, where he played last season, but whether he does might depend on how Dixon does against the Titans on Sunday.
Leftwich went through a full practice for the first time Friday and is listed as probable for this weekend's game.
Dixon won't say he was playing under restraints, but rather that he was more concerned with managing Pittsburgh's offense.
"I'm just trying to make plays out there, regardless of run or pass," he said. "I'm just taking what the defense gives me. ... It's based on instinct pretty much. There's no real, 'You go, run.' You run when you can."
"He did a great job, I thought, getting better, catching up to the speed of the game," Arians said. "He had some low throws early because he worked too fast. But I'd rather see low than high because high can get intercepted."
In his two NFL starts to date, Dixon is 30-of-52 passing for 381 yards and one touchdown with two interceptions. That's enough to show wide receiver Hines Ward, the Steelers' most experienced offensive starter, that Dixon is capable of handling the job.
"The more reps Dennis gets, the more comfortable he is going to become and the more we can expand our playbook," Ward said. "There is no question you can't replace a Ben Roethlisberger; he is an elite quarterback. Dennis has great talent and it's him just trying to take advantage of the opportunities that he gets. We are going to ride this thing out with him and see how it goes."
Dixon certainly hopes it goes farther than Tennessee.
"Going week to week, as opposed to a year waiting for the next opportunity, I'm ready for it," Dixon said. "I'm going to have fun in the process."
Notes: Needing help on their injury-riddled lines, the Steelers tried out defensive end Baraka Atkins, offensive tackle Allen Barbre and guard Donald Thomas on Friday, a league source told NFL Network insider Jason La Canfora. All three have significant NFL playing experience. ... Left tackle Max Starks (ankle) and nose tackle Casey Hampton (hamstring) didn't practice for a third consecutive day and have been ruled out of Sunday's game. Listed as doubtful are two rookies, linebacker Jason Worilds (shoulder) and wide receiver Emmanuel Sanders (quadriceps). Rookie wide receiver/kick returner Antonio Brown might play after being held out of the season opener. ... Ward was selected to the President's Advisory Commission on Asian Americans and Pacific Islanders, and he will be sworn in at the U.S. Capitol on Tuesday. The commission coordinates with government agencies to involve Asian Americans and Pacific Islanders in federal programs for business, agriculture and economic development. Ward's Helping Hands Foundation helps mixed-race children who face discrimination, especially in South Korea. Ward's mother is Korean.
The Associated Press contributed to this report.