BALTIMORE -- Bud Norris allowed one run into the sixth inning and seldom-used first baseman Steve Pearce had three hits and two RBIs, including a key tying single, as the Baltimore Orioles beat the Pittsburgh Pirates 5-1 on Thursday in the first game of a doubleheader.

The Pirates had won their last nine interleague road games after going a major league-best 15-5 overall in interleague games in 2013.

Pearce drove in a run with a single in the sixth to give the Orioles a 4-1 lead against Pittsburgh starter Charlie Morton (0-4), who has not won an interleague game since June 14, 2008. Right fielder Nick Markakis gave the Orioles a 5-1 advantage with a solo homer in the seventh against Jeanmar Gomez.

The Orioles had scored three runs in the fifth to take a 3-1 lead. Pearce drove in a run with a bases-loaded single and third baseman Ryan Flaherty followed with a two-run single, also with the bases loaded, to make it 3-1.

The Pirates had taken a 1-0 lead in the third on a two-out RBI single by third baseman Pedro Alvarez.

Norris (2-2) allowed one run and seven hits in 5 1/3 innings before reliever Ryan Webb retired the final two batters in the sixth with two runners on.

Pearce, batting in the No. 8 spot, entered the day 1-for-7 with no RBIs this season for the Orioles. He was signed by the Orioles as a free agent on Tuesday after he was designated for assignment April 22 and released Sunday.

Baltimore closer Tommy Hunter came on with two on and two outs in the ninth to get the final out. First baseman Gaby Sanchez struck out looking on a 97 mph fastball on the outside part of the plate.

NOTES: The game was delayed 21 minutes by rain in the top of the fifth inning. ... Before the first game of the doubleheader, the Orioles activated 3B Manny Machado from the 15-day DL and sent utility man Steve Lombardozzi to Triple-A Norfolk. Machado missed the first 24 games of the season after having an arthroscopy and open construction on the medial patellar femoral ligament on Oct. 14, 2013. Machado was not in the starting lineup for the first game, but manager Buck Showalter plans to start him in game two. "We were not going to play him 18 innings in his first day back," Showalter said. Lombardozzi hit .292 in 72 at-bats in his first season with the Orioles. ... Both teams had off days on Monday and then had their games rained out here Tuesday and Wednesday. So what is like to have three days off in a row in April? "Stay focused on what you can control," Pirates manager Clint Hurdle said. ... Pirates LHP Wandy Rodriguez made a rehab appearance for Double-A Altoona of the Eastern League on Thursday and gave up four runs in 3 1/3 innings in a 9-4 win at Erie, a farm team of the Detroit Tigers.