The lanky right-hander, who is scheduled to start Game 7 (if necessary) for the Angels on Sunday night, silenced the Yankees and electrified the crowd with a 1-2-3 eighth inning that included two strikeouts, the latter of which came against Derek Jeter to end the frame.
Weaver was one of several heroes for the Angels in a thrilling 7-6 victory in Game 5 of the American League Championship Series.
"Oh, that fired me up," said Angels center fielder Torii Hunter. "Weaver came in throwing 93 [mph]. He had the cartoon curveball working, the changeup working. He was pretty excited."
A 3-1 deficit in the series has now been reduced to 3-2, as the Angels will try to come all the way back in New York, starting with Saturday night's Game 6 at 4:57 p.m PT.
Weaver played his part to create that opportunity.
"It was a hair-pulling experience," Weaver said. "They get you up, the nerves kick in a little bit. After that, you find out that you're going into the game and you try to get in a zone and relax as much as possible. It was fun. It was a good time for me, and hopefully we can take this and go with it in New York and get some momentum going."
Weaver, who threw just 11 pitches, eight of them strikes, seemed to have no doubt that he will be able to start Game 7 if the series extends that far.
"Absolutely," he said. "It's all hands on deck. You have to be ready for anything right now. Whatever their decision is for Game 7, I'm OK with it. In my mind, I'm getting ready to pitch Game 7. We've got to get one more first. We'll take one game at a time."
Weaver had turned in only one relief appearance in his entire career, that coming in extra innings of Game 3 of the Division Series against the Red Sox last year.
This was an entirely different type of situation. The Angels had just put together a stirring three-run rally in the bottom of the seventh to take the lead. This, after the Yankees had produced six runs with two outs in the top of the inning.
Angels manager Mike Scioscia badly needed his next reliever to keep the momentum on his team's side, and Weaver did just that.
"He did a great job," said ace John Lackey, who started the game for the Angels. "Especially after we scored runs. Throwing up a zero after your offense scores is always a huge momentum shifter. To come in and throw strikes, he did a tremendous job for us. For sure, it was a big spot, and he came up big."
Just how big Weaver's shutdown inning was might not be known until the series is over.
"We've got some room to go, and hopefully we take this and go with it in New York," Weaver said. "I like being a starter, but I'm here to do anything. It was fun for me, but I'll try to stick to the starting thing."
If the Angels can win Game 6, Weaver's next start will be the biggest of his career.
Ian Browne is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.