HOUSTON -- JJ Bleday showed off his defensive skills, and Esteury Ruiz continued to produce at the top of the lineup for Oakland on Friday night.

Bleday robbed Houston hitters of extra bases on two separate occasions, and Ruiz was 2-for-4 with a walk, a run scored and a stolen base in Oakland’s 5-1 loss to the Astros at Minute Maid Park.

First, Bleday ended a quick first inning with a leaping grab to take a hit from Yordan Alvarez.

“That ball took off,” Bleday said. “Everyone knows he hits the ball hard, and it took off an extra foot. I was able to get there and make a good route to it.”

Then Bleday robbed Martín Maldonaldo of a run-scoring extra-base hit with another diving catch to end the fourth. After the Astros loaded the bases off starter Ken Waldichuk, Maldonaldo drilled a 2-0 pitch to the left-center-field gap, but Bleday raced to his left and dove for the snag to keep the A’s within a run.

“I was just trying to play off that wall,” Bleday said. “That wall is kind of weird in left field. It’s not the norm, so I kind of set myself up. Maldonaldo likes to go that way. Just took a good route. I thought I overran it for a second, but I was able to catch it.”

Oakland Manager Mark Kotsay said Bleday played a great left field.

“Bases-loaded catch in the gap saved the game at that point,” Kotsay said. “You can’t ask for a better play than that. A couple of good signs from the guys tonight, and we’ll continue to look forward to that.”

Bleday’s defensive gems were not Oakland’s only web gems, as Shea Langeliers threw out Jeremy Peña trying to steal with a pinpoint throw in the second, and Ramón Laureano sprinted in to make a sliding grab in right field on a José Abreu fly ball in the seventh.

Ryan Noda added a nifty over-the-shoulder catch in foul territory to retire Maldonaldo for the second out in the eighth.

Oakland entered the game tied for second in the Majors with 30 errors.

“It’s a focus for us,” Kotsay said of the defense. “We’ve talked about improving our defense, talked about how important it is to catch the baseball.”

Ruiz continued his torrid May, with two singles in his first two at-bats and his MLB-leading 21st stolen base. He also scored Oakland’s lone run on an RBI double from Langeliers in the third.

“Ruiz has done a great job,” Kotsay said. “For first-year full season, he continues to impress, he continues to take good at bats. He gets on base and is stealing bases.”

Ruiz, a rookie, is hitting .320 (24-for-75) with 10 stolen bases in 17 games in May. Over the last eight games, he is 12-for-34. He leads all rookies in hits (51) and stolen bases.

“It gives us confidence, because you know when he gets on, he’s going to be aggressive on the basepaths and steal some bases,” Bleday said. “He’s going to do everything he can to put us in an opportunity to score. He plays so hard on both sides of the field.”

Unfortunately, the injury bug continues to bite the A’s, as Waldichuk exited in the sixth with a mild left calf strain after throwing a pitch to Jeremy Peña. He will be re-evaluated on Saturday.

Waldichuk said he felt it in his last two pitches, and Kotsay recommended exiting the start as a precaution. The lefty said he didn’t think the injury was serious.

Waldichuk had an up-and-down evening, allowing four runs (three earned) on five hits with three strikeouts and five walks. The lefty walked at least five for the third straight start.

“I thought Ken went out there and grinded,” Kotsay said. “He got hurt tonight in really the middle of the order. The three, four, five guys. A couple breaking balls that just hung in the zone for Tucker and Alvarez. They took advantage of them.”

Waldichuk said he had bad execution and issued too many walks, but felt like he is trending in the right direction.

“I feel like I was filling up the zone a little more despite the walks -- those temporary lapses in focus,” Waldichuk said. “I felt like I was definitely trending positively.”