PITTSBURGH -- The Pittsburgh Pirates wore throwback uniforms on Tuesday night to honor the 40th anniversary of the club's 1971 World Series title.
The new duds provided plenty of inspiration to Pittsburgh's slumping offense.
"We average nine runs a game in these unis," Pittsburgh manager Clint Hurdle joked.
Or, two more than the total the Pirates managed during their recent slide.
"(Resop) has done the job a number of times this season with runners on base, has come in right on right and get people," Hurdle said.
Resop keyed another sparkling performance by Pittsburgh's bullpen. A night after relievers logged seven effective innings in an 8-3 loss, Resop, Tony Watson, Jose Veras and Tim Wood held Baltimore scoreless after the Orioles cut it to 5-3 in the fifth and allowed the Pirates to break it open late.
"All these guys have pitched a lot of innings in the last week and pitched extremely well and it (was) time on offense that we gave them a little breathing room," Hurdle said.
Baltimore's Jeremy Guthrie (2-9) settled down after a rocky first inning but dropped into a tie for the American League lead in losses. He gave up six runs -- five earned -- while walking three and striking out two in 6 1/3 innings and didn't appear to be bothered by a minor back strain that cut short his last start.
"I didn't make very good pitches, I didn't have very good stuff," Guthrie said. "My offspeed was not crisp, and the fastball, a lot of mistakes were made with it and they came out swinging."
Baltimore manager Buck Showalter didn't blame Guthrie but an offense that left 10 runners on base, including six in the first four innings as the Pirates took a big lead.
"We had some opportunities," Showalter said. "I'm proud of the way (Guthrie) gave us some innings. He hung in there."
The retro look was part of a festive night in which the Pirates feted the championship team that beat the Orioles in seven games four decades ago. A pregame ceremony honored a team that included Hall of Famers Roberto Clemente and Bill Mazeroski.
Those heady days are a lifetime ago for both franchises. Baltimore and Pittsburgh have combined for 31 consecutive losing seasons, though both clubs have shown signs of progress this spring, particularly the Pirates.
Pittsburgh improved to 36-37 heading into Wednesday's series finale by breaking out of a mini-slump. The Pirates' nine runs were two more than they scored during their four-game slide.
They busted out by doing the little things. Jones hit a two-run double in the bottom of the first then Andrew McCutchen -- batting clean-up for just the second time this year -- dropped a bunt to move over Jones and he scored on a sacrifice fly by Walker.
"We're not a team that is going to hit three-run homers all the time," McCutchen said. "We've got to play small ball. Regardless of where we are in the lineup, where I am in the lineup, I'm going to continue to play the game the right way."
McDonald tried to hang around long enough to pick up his sixth win of the season but never looked completely comfortable on a muggy night.
Home runs by J.J. Hardy and Adam Jones pulled Baltimore within 5-3 in the fifth. A single and a walk put the tying run on first base with two outs when Hurdle came to the mound to pull McDonald after 104 pitches and one out short of qualifying for the win. He gave up three runs, walked four and struck out three in 4 2/3 innings.
"His stuff was up, his command was pretty much gone and we needed to win the ballgame," Hurdle said.
The 26-year-old bent his head while handing the ball to Hurdle and tugged at his cap before slowly jogging off the field.
"Five innings, I don't think, is good enough, I think I need to go deeper in games," McDonald said. "I think a lot of times I get myself in trouble."
Resop escaped the jam by striking out Robert Andino.
Pittsburgh added a run in the seventh on an RBI single by Paul to chase Guthrie, who has won just once in his last 14 starts. The Pirates then broke it open in the eighth off reliever Brad Bergesen, highlighted by a two-run double by Walker.
Guthrie battled through 97 pitches and appeared to have no lingering effects from a back strain discovered after he worked five near perfect innings against Toronto last Thursday.
He wasn't nearly as sharp this time.
Pittsburgh RHP Charlie Morton will skip his next scheduled start on Sunday against Boston because of arm fatigue. McDonald will start in Morton's place. Morton is 2-2 with an 8.50 ERA in June. ... Showalter said 2B Brian Roberts will be out at least through the All-Star break while he continues to deal with concussion-like symptoms. ... Baltimore's Nick Markakis extended his hitting streak to 12 games with a single in the fifth.