BALTIMORE (AP) -The Washington Nationals ' poor outfield play proved costlier than the Baltimore Orioles ' baserunning blunders.

Luke Scott homered, Melvin Mora hit a tiebreaking double in the fifth inning and the Orioles rallied past Washington 5-3 Friday night for their sixth win in seven games and third consecutive come-from-behind victory.

''Obviously it's not the way you want to draw it up, playing from behind all the time, but you've got to do an awful lot of little things right to get yourself back in,'' Baltimore manager Dave Trembley said.

Washington's fielding woes were to blame for a wild two-run fifth that broke a 3-all tie. Two Orioles baserunners were thrown out and Washington outfielders twice misjudged fly balls.

Brian Roberts led off with a triple off the wall in right field against Shawn Hill (0-1). Roberts, who reached third when the ball caromed past Elijah Dukes and into short right, scored when center fielder Lastings Milledge misplayed Mora's fly ball to right-center.

Milledge appeared indecisive on a catchable drive and the ball landed just outside the webbing of his glove. Neither Milledge nor Dukes called for the ball and Milledge said he wasn't sure he could even reach the fly.

''We were in a shift and they hit it where we weren't,'' he said. ''I have a lot to learn yet. I'm not going to lie to you about that.''

After Nick Markakis struck out, Mora was tagged out during a rundown between second and third when Aubrey Huff hit a sharp comebacker to Hill. Kevin Millar followed with an RBI single to center, but was thrown out trying to advance after Huff scored for a 5-3 Orioles lead.

Left-hander Garrett Olson (3-0) struggled through five innings but remained undefeated in four starts since being recalled from Triple-A Norfolk on April 29. He allowed three runs and nine hits while striking out three.

The first three Nationals hitters reached against Olson, producing a quick 2-0 lead. Felipe Lopez led off with a single, moved to third on Cristian Guzman 's double and both scored on Ryan Zimmerman 's liner to left, the first of his three hits.

''You don't look forward to those outings, but sometimes it happens,'' Olson said. ''I didn't feel like I had my sharpest stuff out there tonight, but I tried to keep attacking the zone. When that happens, you have your defense behind you.''

The Nationals wasted an opportunity in the fourth, when they loaded the bases with no outs on singles by Aaron Boone , Milledge and Jesus Flores . Olson struck out Wily Mo Pena , got Dukes to hit a sacrifice fly and coaxed a rally-ending fly ball from Lopez.

''Olson learned how to pitch tonight without his best stuff and I give him a lot of credit, because I don't know whether he would have been able to do that last year,'' Trembley said. ''He competed.''

Matt Albers worked two scoreless innings, Jim Johnson struck out the side in the eighth and George Sherrill got the final three outs for his 16th save in 18 tries.

Hill allowed five runs - four earned - on eight hits, walked two and struck out three.

''He didn't have his breaking ball. Basically, it was nonexistent,'' Washington manager Manny Acta said. ''They waited on his fastball, and he didn't have control of that either.''

Baltimore erased the 2-0 deficit in the second when Markakis hit into a bases-loaded fielder's choice, and second baseman Lopez's relay to first for an attempted double play sailed wide, scoring another run.

After Dukes restored the Nationals' lead in the fourth, Scott tied the game with a solo homer to right-center, his third of the year, in the bottom of the inning.

Notes: Washington activated 1B Dmitri Young (sprained lower back) from the 15-day disabled list Friday. Young went 1-for-4 as the Nationals' designated hitter. ... Johnson has not allowed any of his 12 inherited runners to score this season. ... Zimmerman is 17-for-46 (.369) with 11 RBIs in his last 10 road games.