With his deep bullpen fully rested and Nathan Eovaldi having given up his share of hard-hit balls, Joe Girardi was taking no chances with a one-run lead.
The manager summoned lefthander Chasen Shreve to face the tough, lefthanded hitting Josh Reddick with one out in the fifth, the start, Girardi hoped, of a final 4 2/3 scoreless innings by the bullpen.
Shreve struck out Reddick but Billy Butler jumped on a first-pitch fastball and sent a game-tying homer to left.
It was the first of two hiccups by Yankees relievers that cost them in a 4-3 loss in 10 innings to the A's Tuesday night in front of 32,337 at the Stadium.
As surprising as the homer allowed by Shreve was -- the effective lefthander had allowed just two this season -- it paled in comparison to the 10th-inning bomb given up by Dellin Betances, named Monday to the All-Star team a second straight season.
After a scoreless ninth, the righthander -- who allowed a game-tying two-run homer to Steven Souza Jr. of the Rays on Saturday, the first home run he allowed since last August -- hung an 0-and-2 curveball to Brett Lawrie, who hooked it just inside the leftfield foul pole for his eighth homer of the year to make it 4-3.
Tyler Clippard walked Brett Gardner and Alex Rodriguez in the bottom of the 10th, giving Mark Teixeira a chance to win or tie it. Teixeira, the AL leader in RBIs with 59, got ahead 3-and-0 before striking out, earning Clippard his 16th save.
A's righthander Sonny Gray, who entered the game 9-3 with a 2.09 ERA, was not himself after an 11-day layoff. Gray was erratic from the start and allowed three runs, six hits and three walks over seven innings.
Eovaldi, 3-0 with a 2.08 ERA over his previous three starts, kept the damage to a minimum over 5 1/3 innings. The righthander allowed two runs, six hits and one walk. He was removed after his 86th pitch of the night resulted in a ground smash by Ben Zobrist to second for the first out of the sixth.
The A's got to Eovaldi in the first. Catcher Stephen Vogt, named to the All-Star team Monday, singled with one out. Eovaldi got Zobrist to ground out but Reddick, who entered the game with an MLB-best 32 two-out RBIs, chopped a single back up the middle that brought in Vogt to make it 1-0.
The Yankees came right back in the bottom half against a clearly rusty Gray, whose long break between starts came because of an illness that caused him to be skipped.
Brett Gardner sent a 1-and-0 pitch to center. Gray walked Chase Headley on four pitches. Gray fell behind A-Rod 3-and-0 before he flew to short center. Teixeira struck out but Brian McCann dumped a broken-bat single to left to bring in Gardner. Garrett Jones then beat the overshift with a shot to right to score Headley, making it 2-1.
The A's drew even in the third. Marcus Semien and leadoff man Billy Burns started the rally with consecutive singles. Vogt made it three straight hits, his single to right bringing in Semien to tie it at 2. But with runners at the corners, Eovaldi kept it there, striking out Zobrist and getting Reddick to ground into a 4-6-3 double play to end the inning.
The Yankees took the lead again in the fourth. McCann walked and Jones singled to left. Gray got Chris Young to ground into a 6-6-3 double play but Didi Gregorius jumped on a first-pitch 94-mph fastball for an RBI single that made it 3-2.