As a first baseman for 13 big-league seasons, Lyle Overbay built a memory bank of fielding plays. Little can surprise him. He can visualize most every scenario, and how he would handle the moment.

In his new life as an outfielder, an experiment that cost the Yankees on Tuesday night against the Athletics, he lacks similar resources. Most everything is new to him.

“Guys who have played in the outfield enough, they can kind of react,” Overbay said over the weekend in Seattle. “Just like me at first [base].”

When Andy Pettitte returned from the disabled list on June 3, the Yankees bucked conventional wisdom. Rather than designate Overbay for assignment – or option infielder David Adams – they shipped outfielder Brennan Boesch to Triple A. With Boesch gone, the team opted for an unexpected scheme: Overbay would play right field, a position he had never tried before in the majors.

The idea worked for a few reasons. The team hoped to retain Overbay as an insurance policy for first baseman Mark Teixeira and designated hitter Travis Hafner. They also understood Overbay was still a useful offensive player, especially against right-handed pitchers. Overbay has an .839 on-base plus slugging percentage against righties.

After Boesch’s demotion, Overbay started three games in a row at Yankee Stadium. He did not cost his team in the field. And he continued to be a useful, left-handed hitter. But he sat out the entirety of the four-game series in Seattle. Manager Joe Girardi appears reluctant to use Overbay away from home, where right field is cozy.

In the second inning on Tuesday, with Overbay playing right, the Yankees received a reminder of the risk they took. With Josh Reddick at second base, CC Sabathia faced catcher Derek Norris. He stuffed a 3-1 fastball low in the zone, and jammed Norris. The resulting pop fly drifted toward the right-field line.

Both second baseman Robinson Cano and Overbay gave chase. Overbay assumed Cano would be there, he would say later. This assumed knowledge dissuaded him from diving. Instead, the baseball dropped between them.