Orioles outfield situation is beginning to shake out

The top of the Orioles starting lineup for the first game of Sunday’s split-squad doubleheader included four players who are competing for a big league job in the outfield .. or at least part of one.

Colby Rasmus, who singled home the first run in a 7-3 victory over the Boston Red Sox at jetBlue Park, looks like he’ll get lots of playing time in right field when the season starts. The futures of Alex Presley, Joey Rickard and Danny Valencia are much more uncertain.

Manager Buck Showalter has been lavish in his praise of the way Rasmus has worked to catch up after signing with the club a week into training camp.

“Rasmus is very professional,’’ Showalter said. “Each day, leaving him back, he…