LEADING OFF: Red Sox struggling, Jansen back at Coors FieldBoston Red Sox's Mookie Betts reacts after striking out looking in the sixth inning of a baseball game against the Oakland Athletics Thursday, April 4, 2019, in Oakland, Calif. (AP Photo/Eric Risberg)
OAKLAND, Calif. (AP) -- When the reigning AL MVP openly regrets challenging you, that's pretty high praise.
Laureano tossed out three runners as the A's took three of four in the series.
''Rarely do you see three impactful plays like that in a series, because sometimes they stop running on you, but they continued to be aggressive on him, and every time he made a different play from the one before - but all big plays in the course of a game,'' A's manager Bob Melvin said.
''It's tough to keep finding adjectives for Ramon's throwing, but it's one of a kind,'' he said.
Mookie Betts led off the Red Sox ninth inning with a walk and tried to take third when Andrew Benintendi followed with a bloop single. But Laureano charged the ball hard and threw on the run to catch Betts, with the out call being upheld on replay.
''I should have known,'' Betts said. ''He's pretty much thrown everybody out. That's what my instincts told me to do and I should have let myself know before anything even happened that my run meant nothing.''
On Tuesday night, Laureano threw out Xander Bogaerts at third as he tried to stretch a double in the ninth inning of a game Oakland won 1-0. On Monday night, Laureano threw out Bogaerts at the plate early in a 7-0 win for the A's.
The 24-year-old Laureano made his major league debut last year. He now has 12 assists in only 57 games in the outfield with the A's.
''It's a bad decision and he knows it,'' Red Sox manager Alex Cora said of Betts' base-running blunder.
''The three plays were bang-bang plays, but that one right there can't happen and he knows it. He came up to me, and for how great a player he is, he makes mistakes and he owned it. He came up to me and said 'that's my fault.'''
Why would anyone challenge Laureano?
''They might, I don't why they would, but they might,'' Stephen Piscotty said. ''I was shocked to see it ... The guy's got a cannon and he's laser accurate.''
Piscotty led the A's offense as he went 4 for 4 with a home run, double and five RBIs to help Oakland win for the fifth time in six games.
The Red Sox fell to 2-6, the worst start for a defending World Series champion since the stripped-down Marlins struggled in 1998. J.D. Martinez homered for Boston.
Brett Anderson (2-0) gave up three runs and eight hits and four walks in 5 1/3 innings.
Anderson walked home two runs in the first inning. Martinez connected for his third home run in the third, making it 3-0.
The A's tied it in the third on Piscotty's three-run homer off Eduardo Rodriguez (0-2). Rodriguez gave up six runs and eight hits and three walks in 3 2/3 innings.
Piscotty got a gift two-run double with two outs in a three-run third. Oakland had runners at second and third when Piscotty hit a fly to the warning track that split Jackie Bradley Jr. in center and Betts in right - neither outfielder called for the ball and it landed between them, bouncing over the fence for a double.
''The whole game was unusual,'' Cora said when asked about the outfield miscommunication.
''You didn't see that last year, but last year was last year ... We have to play better, that's the bottom line.''
A's relievers Lou Trivino, Joakim Soria and Liam Hendriks combined for 3 2/3 innings of shutout ball.
Martinez has hit safely in all eight games for Boston. ... Rodriguez recorded his 500th career strikeout in the first when he got Khris Davis swinging to end the inning. ... The Red Sox are 16-38 in their past 54 games at Oakland and 3-13-1 in their past 17 full series at the Coliseum.
Red Sox: 1B Steve Pearce (left calf strain) was activated from the injured list and was in the lineup. The 2018 World Series MVP was 1 for 4 and struck out three times.
Athletics: A day after being hit by a pitch on his surgically repaired left wrist, 3B Matt Chapman was out of the lineup on Thursday but came into the game in the eighth inning. Manager Bob Melvin said the move was precautionary. Chapman underwent left wrist surgery in 2015. ... Utilityman Chad Pinder took Chapman's spot at third. ... 1B Matt Olson (right hand surgery) took ground balls for third time on Thursday.
Red Sox: RHP Rick Porcello (0-1, 13.50 ERA) will start Friday's series opener in Arizona. Porcello gave up nine runs (four earned) in 2 2/3 innings in his season debut on March 31 against Seattle.
Athletics: RHP Frankie Montas (1-0, 1.50) will start Friday's series opener in Houston. Montas gave up one run in six innings of one-hit ball in his first start against the Angels on March 31.
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