BALTIMORE -- J.J. Hardy missed the season's first 25 games due to a shoulder injury he sustained in spring training. The shortstop struggled at the plate since his return, but he gave the Baltimore Orioles a big hit Thursday.

Second baseman Steve Pearce hit a first-inning grand slam, but the Orioles needed a tiebreaking single from Hardy in the eighth to pull out a 5-4 victory over the Seattle Mariners.

Hardy went 1-for-4 in the victory, giving him a .196 average through his first 13 games.

"It's nice to get hits when you're feeling like I feel right now," Hardy said. "Every day I'm making adjustments. I'm just trying to (find) something that feels good and have something to work off of, so it's definitely nice getting hits when you're not feeling great."

The hit that made Hardy feel a little better came against right-hander Danny Farquhar (0-3) in a 4-4 tie. First baseman Chris Davis led off the eighth with an infield single and went to second when Pearce grounded back to the pitcher.

Hardy then lined a single to center, and Davis beat the throw from center fielder Justin Ruggiano to give the Orioles a 5-4 lead.

"That was a hanging cutter down the middle," said Farquhar, who lost for the second time in the series. "I was trying to get it down and away."

Tommy Hunter (2-1) got the win after the right-hander escaped a bases-loaded situation with two outs in the eighth, his only inning.

Left-hander Zach Britton closed it in the ninth, earning his ninth save.

The Orioles (18-20) won two out of three in the series and will head to Miami for a weekend set with the Marlins. Orioles manager Buck Showalter said he hopes the latest victory could give his team a boost.

"It was actually one of those games when you gain some experience, you kind of get on the plane feeling good about doing something that not just anybody can grind through," Showalter said. "It was one of those games that we've been good at over the last three years. It may not look aesthetically pleasing, but you end up with a W."

Pearce's homer gave the Orioles an early 4-0 lead, but they could not hold it as the Mariners (18-22) kept chipping away in a game that was interrupted by a 2-hour, 5-minute rain delay in the third -- plus a 12-minute rain delay at the start. The contest didn't end until about six hours after it began.

The Mariners scored a run in the second and two in the fourth, then tied it on first baseman Logan Morrison's bases-loaded walk against right-hander Darren O'Day in the seventh.

However, Seattle wasted a number of scoring chances, stranding 13 and going just 3-for-15 with runners in scoring position.

"We did have opportunities," Mariners manager Lloyd McClendon said. "We just couldn't really get the big hit to really put us over the hump. We fought back, tied that ballgame up. We really battled (but) just couldn't come through."

Baltimore loaded the bases with two outs in the first against Mariners starter J.A. Happ. Pearce came up and golfed the first pitch into the left field seats for his first career grand slam and an early 4-0 lead.

Pearce has struggled through much of the first two months but is hitting better recently. He went 1-for-3 to raise his average to .198.

"(The grand slam) was great, considering how I've been swinging the bat lately," Pearce said. "Hopefully, this gets me started on the right foot moving forward."

The Mariners got a run in the second off right-hander Chris Tillman on catcher Welington Castillo's sacrifice fly in his first at-bat with the team.

The rain delay then brought in left-hander Brian Matusz from the Baltimore bullpen in the fourth, and he ran into trouble. Matusz walked No. 9 hitter Chris Taylor -- who entered the game batting .132 -- to load the bases, and pinch hitter Rickie Weeks followed with a two-run single to left to make it 4-3.

Seattle tied the game in the seventh. The Mariners loaded the bases with no outs before O'Day retired two in a row and threw two quick strikes to Morrison. However, Morrison battled his way back for a game-tying walk.

NOTES: Major League Baseball made a scoring change from the Orioles-Angels game on Saturday, removing an error charged to Baltimore 3B Manny Machado and giving LF Matt Joyce a hit. ... The Orioles' Caleb Joseph, who is hitting .260, fourth among American League catchers, got the day off. ... C Welington Castro made his first start for the Mariners and drove in a run in his first at-bat, a sacrifice fly in the second inning. ... Seattle 3B Kyle Seager was ejected by plate umpire John Tumpane in the fifth inning after arguing a called third strike. It was Seager's first career ejection.