BALTIMORE -- Craig Gentry usually helps the Baltimore Orioles with his defense and speed. On Monday night, though, he made a difference with his bat.

Gentry hit a walk-off single with two outs in the ninth inning to give the Orioles a 2-1 victory over the Kansas City Royals in the opener of a three-game series.

Caleb Joseph started the winning rally with a one-out single to center field off Joakim Soria (4-3). Joseph advanced to second on a two-out single by Ruben Tejada.

Gentry followed with a soft single to center that drove in Joseph easily from second. It was Gentry's first walk-off hit and Baltimore's seventh walk-off win this year.

"It has been a battle, a big grind, not only this year but the last few years," Gentry said. "And to come out here and something like this happens to me, it's pretty amazing."

Gentry now has a .200 average in 50 games, mostly as a fill-in. However, Orioles manager Buck Showalter is a fan of Gentry, and the skipper made that clear after the game.

"Anybody who knows Craig, he's always on," Showalter said. "He's the type of guy you want on the team. That's why we wanted to bring him in."

The Royals thought that Showalter might pinch-hit for Gentry -- who batted ninth -- or in other spots in the bottom of the lineup, but that did not happen as the Baltimore skipper's decisions paid off.

The victory was the 1,480th of Showalter's career, tying him with Earl Weaver for 24th on the all-time list.

The Orioles (51-54) won their third straight and posted their first victory over the Royals this season. Kansas City (55-49) swept Baltimore in an earlier three-game series.

Zach Britton (1-0), pitching for a third day in a row, picked up the win thanks to a scoreless ninth. There had been numerous rumors that Britton might be traded to a team such as the Houston Astros or Los Angeles Dodgers, but that never took place, and the closer will stay in Baltimore.

Neither team could do much offensively on a night dominated by the pitchers.

Ubaldo Jimenez gave the Orioles a second consecutive quality start for the first time this season. The right-hander struggled in the first few innings but settled down after that, allowing one run and five hits in seven innings.

Jimenez struck out six and walked two, leaving with the score tied at 1.

Kansas City starter Danny Duffy matched Jimenez, yielding one run and seven hits in seven innings. The left-hander retired the final seven Orioles he faced, struck out six and walked just one.

The Royals took an early lead thanks to two first-inning doubles off Jimenez. Lorenzo Cain got the first one before Eric Hosmer added the second with two outs.

Baltimore tried to take the lead in the second inning, but Cain robbed Chris Davis of a two-run homer with a leaping catch at the center field fence.

"It definitely would have been a homer," Cain said. "The walls are short here. I didn't have to jump high for it, but I jumped just enough to make the play and pull it back it in."

The Orioles tied it with a two-out rally in the fifth. Manny Machado lined his second double of the game and scored on a soft single to center from Jonathan Schoop.

Both starting pitchers kept the opposing offenses quiet, which set up the late-game dramatics.

"It was a well-pitched night," Royals manager Ned Yost said. "It's pure baseball. It was a great game. You've got to give credit to both starting pitchers."

NOTES: The Orioles acquired INF Tim Beckham from the Rays for a minor league pitcher. Beckham likely will jump in at shortstop as the team moved starting SS J.J. Hardy (broken right wrist) from the 10-day disabled list to the 60-day DL. ... RHP Jeremy Hellickson joined the Orioles and will start Wednesday's series finale with Kansas City. He came to the team in a deal with the Phillies on Friday. ... The Royals did not make any trades Monday but acquired OF Melky Cabrera over the weekend. He made his debut and went 0-for-4. ... The Tuesday probable starters are Royals RHP Ian Kennedy (4-6, 4.43 ERA) and Orioles RHP Dylan Bundy (9-8, 4.53).