Oakland catcher Derek Norris prepares to tag out Baltimore’s Nelson Cruz on an attempted steal of home in the 10th inning of the Orioles’ 4-3 loss to the A’s in 11 innings on Friday. (Patrick Semansky/Associated Press)

One constant for the Baltimore Orioles over the last couple years has been the club’s outstanding defense, anchored by shortstop J.J. Hardy.

Hardy had just one error heading into this week, but he committed three on Thursday and then made a crucial error in the 11th inning Friday as the Orioles lost, 4-3, to the Oakland Athletics.

Reliever Evan Meek (0-2), who came up from Class AAA Norfolk on Friday to provide an extra arm in the bullpen, was the loser by allowing an unearned run in the 11th.

Pinch-hitter John Jason started the inning with a hit to center field that he hustled into a double. Meek picked up a strikeout and then Alberto Callaspo hit a hard grounder to short that Hardy fumbled. The next batter, pinch-hitter Stephen Vogt, singled to left for the go-ahead run.

A’s closer Sean Doolittle struck out the side for his eighth save in a game that Baltimore could have won twice in the previous inning.

Playing before a loud, announced Camden Yards crowd of 28,076 — and at home for the first time since May 25 — the Orioles (30-29) lost for just the second time in six games. This one came against an Oakland club (38-23) who entered the night with the best record in the American League. The Orioles are 5-3 in extra innings and 12-9 in one-run contests.

They tried almost everything to end the game in the 10th, including a surprising attempted steal of home by Nelson Cruz.

Nick Markakis led off the 10th with a single against Fernando Abad (1-2), moved to second on a sacrifice bunt and then, after Cruz was issued his fifth intentional walk of the season, Adam Jones singled to right.

Markakis rounded third and tried to score, but right fielder Brandon Moss made a perfect throw to home and catcher Derek Norris tagged Markakis just as he stretched his hand to the plate.

Orioles Manager Buck Showalter came out to argue the call and the umpires reviewed the play before upholding the out.

With Chris Davis at bat and a 2-2 count from Abad, Cruz attempted to steal home, but was thrown out to end the inning.

Things got chippy in a weird exchange in the third inning between two of the best third basemen in the American League, Manny Machado and Oakland’s Josh Donaldson.

With two outs and Machado on second, Jones hit a ball to Donaldson, who gloved it. As Donaldson approached the runner, Machado attempted to avoid the tag and was off-balance when Donaldson slapped him on the chest with his glove.

Machado stumbled and fell backward. He then tossed his helmet while saying something, causing Donaldson to turn around. The two began jawing at each other, both benches emptied and relievers from both teams headed to the field from the bullpens.

No punches were thrown and order was quickly restored.

Machado then made a great play in the top of the fourth on a dive, spin and throw at third base. In the fifth, his bat did the talking with a solo homer into the Orioles’ bullpen to give the Orioles a 3-2 lead.

The Orioles trailed 2-0 early, but Jonathan Schoop delivered a two-out RBI single in the second and Davis took Oakland left-hander Tommy Milone deep with an opposite field homer in the fifth. It was Davis’s ninth home run of the season, and second in three days.

Baltimore starter Wei-Yin Chen allowed two homers in his first five batters, but after that, the A’s had trouble reaching base against the left-hander, who lasted 61 / 3 innings.

— Baltimore Sun