On Monday, the first-rounder got a taste of things to come, prevailing against a pair of Major Leaguers past and present.
MLB.com's No. 7 prospect, selected third overall in June's Draft, improved to 2-0 in three Pacific Coast League outings after striking out eight batters over six two-run innings in the Aces' 10-2 victory over the host Sacramento River Cats.
The 21-year-old right-hander scattered six hits and issued four free passes in the victory -- his ninth of the season across two levels after going 7-1 with Double-A Mobile. He leads all Minors pitchers with 84 punchouts in 67 1/3 innings.
He held 12-time All-Star Manny Ramirez to two singles in four at-bats, while Cuban defector Yoenis Cespedes was 1-for-3 with a strikeout in his first rehab assignment. Cespedes, who played left field and batted second, smacked a base hit up the middle in the second that was deflected by second baseman Jake Elmore, but he was doubled off first base on Ramirez's fly ball to right field.
Bauer, staked to a 5-0 lead in the second, faced one batter above the minimum through the first two frames. He surrendered two runs on two walks, a single and a double in the third and stranded runners in scoring position in both the fourth and the fifth.
Bauer gave up a two-out single to Stephen Parker in the sixth, but he retired Luke Hughes on his 100th and final pitch before turning an 8-2 lead over to the bullpen. The UCLA product threw 56 pitches for strikes.
Ramirez, who plated Sacramento's first run with a base hit up the middle, is batting .250 with four RBIs in nine games with the River Cats. He has reached base safely in each of his last five contests, but he has also struck out seven times in 32 at-bats and is still waiting for his first extra-base hit.
Ramirez retired from baseball last April following a 100-game drug suspension, but that was later reduced to 50 games on appeal. He is eligible to join Oakland on Wednesday when his 10-game Minors rehab assignment ends, but the club said in a statement Monday that he is not ready.
"We will continue to monitor Manny's progress on a day-to-day basis in hopes of bringing him to Oakland just as soon as he is ready to contribute at the Major League level," assistant GM David Forst said.
"I think, if the guys here are swinging the bats more across the board, you'd like to see him get more at-bats [in the Minors]," A's manager Bob Melvin said earlier Monday afternoon. "I'll leave that up to the people that are watching him and the front office."
Cespedes has been on the disabled list with a strained muscle in his left hand since May 7. If he doesn't suffer any setbacks in Sacramento, he could rejoin the A's at the end of the week.
Through 28 games, Cespedes is batting .245 with five homers and 21 RBIs.