"Daric said he saw [catcher] Kurt [Suzuki] look at the guy coming and felt uncomfortable throwing when he wasn't looking," manager Bob Geren said.
What followed was a costly double-pump throw, one Barton called "a reaction thing."
"When I got the ball and saw him rounding third, I had him by a good bit," the A's first baseman said. "I know Willits is fast, and that was always in the back of my head. By the time I threw it, I knew I didn't have him, but you've got to throw anyway."
The run put the Angels ahead for the first time on the day, and the result was a six-game spread in the American League West as opposed to four -- which would have been the case had Oakland held a 3-2, ninth-inning lead.
"Not a bad position to be in," Geren said, "but obviously four would have been better."
Four. Five. Six. These days, any number not ahead of the Angels is one and the same. So close, yet so far -- even if it's not on the minds of A's players.
"I'm not even thinking about numbers right now," said Jack Cust, who enjoyed a 2-for-2 day with two walks and a solo homer. "We had it right where we wanted it ... but it's baseball and crazy things happen. Hopefully we come back in the second half and keep playing great baseball."
Crazy was not the way the day was supposed to go. After all, the A's had their All-Star on the mound throwing just the way he had all season. Just two days before going to his second career Midsummer Classic, starter Justin Duchscherer threw 7 2/3 solid innings.
The right-hander started the game by not giving up a hit until the third frame, when Maicer Izturis tagged him for a triple. One inning later, the A's pitcher had his 18-inning scoreless streak snapped when Howie Kendrick grounded into a forceout that brought home Vladimir Guerrero.
By that time, though, the A's had gotten two on the board early against starter Dustin Moseley, who was called up from Triple-A Salt Lake on Sunday to start. After Suzuki and Cust boarded with base hits in the first inning, Emil Brown and Carlos Gonzalez followed with back-to-back RBI singles.
In the sixth, Cust provided Oakland with some extra cushion by hitting his 18th homer of the season to left-center to make it 3-1.
Casey Kotchman hit a solo shot of his own in the eighth off Duchscherer to make it a 3-2 game before the ninth-inning dramatics began.
"We had them right where wanted them with the guy on the mound who's done it all year for us," Cust said.
The Angels' late comeback started when Huston Street gave up back-to-back singles to Torii Hunter and Juan Rivera to lead off the ninth before Howie Kendrick tied the game on a sacrifice fly. After Ryan Budde moved Willits -- the Angels' pinch-runner for Rivera -- to second base on a sacrifice bunt, Aybar hit the fateful game-winning single.
"It was about bad breaks, really," Geren said. "Bad luck, bad timing ... when we're in a position to win against a first-place team, though, you gotta see that as a positive.
"It's disappointing, sure, but you have to look at it as ... we were pretty banged up."
One of Oakland's seven players currently on the disabled list, Ryan Sweeney, sure could have come in handy in the bottom of the ninth when the A's had a chance of their own at a comeback. After Gonzalez singled and Mark Ellis walked to open the frame, Barton put down a perfectly placed bunt that moved the runners over and forced reliever Francisco Rodriguez to intentionally walk Jack Hannahan with one out.
With right-handed hitter Murphy due up and the bases loaded, Geren opted to send switch-hitter Rob Bowen to the plate -- a situation lefty Sweeney would have seen if not injured.
"A left-hander has more of an advantage," Geren said. "I felt like [Bowen] would be disciplined."
Bowen was a little too disciplined, as he could only watch a called third strike breeze right by him for the second out of the inning.
"I'd obviously take anything from him right there," Geren said. "I was looking for anything to get one or two runs. Maybe a home run?"
Just minutes later, Suzuki came up empty with the A's second strikeout of the inning that had the Angels celebrating.
And for the A's ... "It just wasn't meant to be today," Geren said.