It started with a plane flight into San Francisco and a speedy cab ride to Oakland, and it ended with an RBI double in the eighth that almost helped the A's stage another dramatic comeback.
Josh Donaldson and Nate Freiman also had RBI doubles for the Athletics, but the Los Angeles Angels came out on top, 5-4, in the series finale on Wednesday.
Tommy Milone matched his career high with 10 strikeouts, but he allowed four runs on seven hits over seven innings.
The day belonged to Montz, though, who was thrown out of Tuesday night's River Cats game at Fresno.
"I was called into the manager's office and I thought I was in for it," Montz said. "Rich Rodriguez, the pitching coach, really tore into me. Then in the middle of a sentence, he said, 'And you're going up to the big leagues,' and I did a double take, and said 'Wait, what?' There were some tears and the coaches all gave me a hug. It was emotional."
He caught an early morning flight to San Francisco and stepped into the Oakland locker room about 45 minutes before the game.
"I touched down at SFO and my agent texted me that I was in the starting lineup," Montz said. "I grabbed the first cab and said how fast can you get me there? I don't think he went under 110 mph the whole way."
Montz was able to take a few swings in the batting cage before throwing on his uniform and stepping into the dugout for the game.
"I had to step out of the batter's box the first time up and calm myself down," he said. "The double felt great. It was nerves time but that's when I felt I belonged here. I want to be here."
C.J. Wilson was just good enough to earn the Angels their first win in six tries against the A's. Wilson allowed two runs on six hits, walking five and striking out five.
The A's were unable to take advantage of Wilson's wildness, leaving six runners in scoring position.
Mark Trumbo hit his third home run in as many days, and Mike Trout and Howie Kendrick each hit solo shots for the Angels.
"Every win is going to be big for us. We have good teams like the Oakland A's," Trout said. "They're grinding, they're playing 100 percent every pitch. You can't take anything away from them. When they're down, they just keep fighting and fighting and fighting. That's what we need to start doing."
Milone gave the A's what they needed going into Thursday's off-day, except for winning the game.
"We only used a couple of guys, and with the day off it will get the bullpen back to reasonable shape," A's manager Bob Melvin said. "We needed him to go deep to save the bullpen. Even though we lost it was a good performance by him."
Milone knew what he had to do.
"I wanted to go as deep into the game as I could," he said. "The bullpen has been out there a lot the last few days. I needed to go out and throw strikes. I felt good throughout the game, it was just a few bad pitches."
The A's scored two runs in the third inning, rallying with two outs. Yoenis Cespedes walked and scored from first on Donaldson's double and Freiman followed with his double.
The A's loaded the bases in both the first and sixth innings, but failed to score.
Gold Glove Award winner Josh Reddick threw out Josh Hamilton at third base to end the eighth inning.