The left-hander who made four September starts last season is trying to add a changeup to his repertoire.
"It's no secret that's something I don't have," Cramer said. "Obviously if I were to make this team or come back up, I'm going to need it."
Miller hung in with a line drive hit right at him from Cleveland Indians infielder Jack Hannahan in the top of the eighth, keeping Cleveland from scoring a tying run.
"To have the nerve to hang in there until it comes out of the sun and make the play, that's a really nice play," A's manager Bob Geren said.
Michael Taylor scored on Kurt Suzuki's two-out hit in the sixth to make it 4-2. Oakland scored the first two runs of the game when Hideki Matsui grounded into a bases-loaded double play and Kevin Kouzmanoff singled in a second run in their half of the first inning.
Masterson, who had an encouraging finish to the season when he went 3-3 with a 2.86 ERA in his last eight starts of 2010, was unconcerned by his struggles.
"It was my first time facing another team and second time against live hitters, so it gets you a little excited," Masterson said. "I wanted to stride a little longer and throw a little harder. I felt good physically. The four-seamer was a little bit high. The sinker was slicing and dicing and moving and grooving just the way it's supposed to."
Note: Cleveland LHP Drew Pomeranz, the Indians' first-round pick at No. 5 overall in 2010, made his debut. He pitched a hitless inning with two strikeouts and a walk. ... Oakland reliever Brad Ziegler pitched a scoreless ninth for his first save of spring training. ... A's OF David DeJesus, who'd been dealing with illness, made his spring training debut, starting in right field. He went 0 for 2.