The A's right-hander, on the losing end of a 4-1 game in Toronto, threw wide of second base after slickly fielding a grounder off the bat of Kendrys Morales, putting runners on the corners with no outs in the second inning. The Blue Jays would score four unearned runs that inning, with Gray needing 32 pitches to make it out of the frame.
"I just went to throw it to second, and I just airmailed it," Gray said. "Looking back, obviously, I wish I had just touched first base and tried to minimize the inning there, but it's one of those quick decisions that was made and, if executed, it's a great play and, if you don't, it kind of got them rolling."
There were no shortage of scouts on hand to see it, though they were also witness to ensuing happenings: Gray allowed just one hit over his final four innings and finished with nine strikeouts in the six-inning, 103-pitch outing.
He's completed at least six innings in each of his last six starts, with his ERA falling to 3.43.
"Other than the one inning, he pitched well," A's manager Bob Melvin said. "He recovered, because his pitch count was up after three innings, and we ended up getting more than what I thought we would get out of him. Just ended up being that one inning, and the error probably had something to do with it."
Gray walked two and yielded five hits on the night, including back-to-back doubles from Ryan Goins and Jose Bautista that led to three of the four unearned runs in the fateful second inning.
"At the end of the day, I made a really costly mistake," he said. "Looking back on it, it's one of those that put us in such a big hole early in the game, it was just a little too deep to climb out of. I take pride in the defensive side of pitching, and today it just really let everybody down."
It's long been assumed that Gray, though under club control through 2019, will be dealt ahead of next week's non-waiver Trade Deadline. The A's are thought to be prioritizing a young center fielder in talks with interested clubs, and an abundance of teams remain in the mix for the right-hander, who finished third in American League Cy Young Award voting in 2015.
The Yankees, Nationals, Astros, Cubs and Brewers have all shown interest in Gray, with the Yankees thought to be making the biggest push for the pitcher, per MLB.com's Mark Feinsand, who reported Tuesday that the two sides were "making progress" in getting a deal done.
"It can be difficult at times," Gray said of the speculation, "but we'll just see what happens."
• Outfielder Jaycob Brugman was held out of the lineup because of neck stiffness, though Melvin said the rookie was available during the game to run.
• Reliever Frankie Montas, delayed in New York by visa issues, was expected to arrive in Toronto late Tuesday evening.
Jane Lee has covered the A's for MLB.com since 2010.