In February, the Baltimore Orioles traded their staff ace, left-hander Erik Bedard. This spring, one of the top pitching prospects in their system, Garrett Olson, another lefty, has moved into the rotation and thrived.

After going 9-7 with a 3.16 ERA in 22 starts last season for Triple-A Norfolk, the 24-year-old Olson returned to the Tides at the end of spring training. Four weeks into the season, however, he was in Baltimore. In his first start on April 29, Olson held the Tampa Bay Rays to two runs over six innings in a 7-4 victory. He earned his first “W,” and today he is 5-1 with a 3.86 ERA.

Olson has been roughed up only once all season -- when he took his only loss at Yankee Stadium on May 21 -- but he’s been even better since the defeat.

In his next two starts, at home against the Yankees and the Red Sox, Olson blanked the Yanks for seven innings and allowed a total of two runs combined. On Thursday, he worked into the seventh inning of a 3-2 road win at Minnesota. Olson has posted a 1.96 ERA and .206 OBA in these starts.

The rebuilding Orioles are sticking close to the .500 mark this spring. Much of the credit goes to Olson and Daniel Cabrera, who lead the staff with five wins each and have combined to go 10-3. The ace is Jeremy Guthrie, who is 3-6 with a 3.40 ERA that is the lowest in the rotation, and he could have six or seven wins with a little run support. All three of his May losses were quality starts.