BALTIMORE (AP) -One year later, Garrett Olson finally appears to have grasped the concept of what it takes to be successful in the major leagues.

Olson took a shutout into the seventh inning, and the Baltimore Orioles ended the Tampa Bay Rays ' six-game winning streak with a 7-4 victory Tuesday night in a surprising duel for first place in the AL East.

Recalled from Triple-A Norfolk before the game, Olson (1-0) gave up two runs and four hits in 6 2-3 innings, walking five and striking out six. The left-hander was summoned after a rainout forced Baltimore to play four games in three days, leaving manager Dave Trembley short of rested starting pitchers.

Olson proved to be the perfect stand-in. He retired the first seven batters and came within one out of blanking the Rays through seven innings in his finest performance in the big leagues. Olson made his debut last season and went 1-3 with a 7.79 ERA in seven starts.

This time, however, he was outstanding.

''I just felt I was more in control, not getting flustered in crucial situations and just trusting myself and making a pitch when I needed to,'' said Olson, who will almost certainly get another shot at filling the void in the rotation left by the injury to Adam Loewen .

''I can tell you Olson showed improvement from the last time we've seen him,'' Trembley said. ''He made some big pitches when he had to, but his mound presence, his poise, his ability to make big pitches was good for him and good for our team.''

Aubrey Huff homered and Melvin Mora had two RBIs for the Orioles, who broke a tie atop the division with Tampa Bay. Both teams usually reside in the lower tier of the standings, but each has gotten off to an unexpected solid start while Boston, the New York Yankees and Toronto have struggled.

Baltimore led 7-0 before the Rays scored four runs in the seventh. A two-out RBI double by Akinori Iwamura chased Olson, and Carl Crawford followed with a run-scoring single off Randor Bierd before B.J. Upton hit his third homer.

But it wasn't enough to ruin a memorable performance by the 24-year-old Olson.

''I thought what he did was he pitched inside better and he worked faster,'' Trembley said. ''Last year when I saw him it seemed like his tempo was really slow and he pitched defensive instead of aggressive. Tonight he looked like he was going to make them hit it.''

George Sherrill , the fourth Baltimore reliever, got three outs for his 10th save.

Tampa Bay's Jason Hammel (2-2) allowed three runs, six hits and four walks in 2 2-3 innings - the shortest of his 28 career starts in the big leagues. The right-hander had gone at least six innings in his previous three starts this season.

''I am very disappointed with myself because I basically took myself out of the game. I was affected by the small strike zone and I let it get into my head,'' Hammel said. ''All the hard work that we put in to get to this point, we took a giant step backward. I am definitely not happy with what happened. And I am 100 percent responsible for this loss.''

After pulling off three-game sweeps of Toronto and Boston, the Rays couldn't sustain the momentum.

''There was a lot of emotion involved today,'' manager Joe Maddon said. ''I don't know if that had something to do with it. We have been very emotional the last six days. I just think we got off to a bad start pitching-wise. It was a nice little six-game run, and let's start another one.''

Hammel escaped damage after walking the bases loaded in the first inning, then allowed run-scoring singles to Mora and Nick Markakis in the second. Both were stranded when right fielder Eric Hinske made a diving grab of Kevin Millar 's opposite-field, two-out liner to right.

Olson worked out of a bases-loaded, one-out jam in the third by retiring Crawford on a fielder's choice and striking out Upton.

Ramon Hernandez hit an RBI double in the bottom half for a 3-0 lead, but Adam Jones fell rounding third base on the play and was an easy out at the plate.

A run-scoring double by Brian Roberts , a sacrifice fly by Mora and a two-run homer by Huff made it 7-0 in the sixth.

Notes: Tampa Bay needs a win Wednesday to earn the first winning April in franchise history. ... Hernandez went 2-for-2 against Hammel and is 7-for-14 lifetime against him. ... Huff set a career high with five homers in April. He had four through May 31 last season.