The call that came into question came on a ball hit by Hunter Pence with two outs in the bottom of the sixth inning, with the Astros leading, 8-2. Pence drilled a fastball from Pirates reliever Jesse Chavez into right field that hit off the padded yellow line on the right-field wall. The ball bounced back to right fielder Steve Pearce, who threw the ball back to the infield as Pence trotted into second.
"As an outfielder, no matter what, play it and maybe the umpire won't see it," Pearce said. "That's what I tried to do. The ball was hit very well. It looked like it hit the very, very top of the wall. It was so close that I just wanted to get it back in. It hopped right back to me, and I just wanted to get it fired in."
Houston manager Cecil Cooper came out to argue the call with first base umpire D.J. Reyburn.
"[The umpire] said he thought it hit the top, the yellow line," Cooper said. "I just said I thought it was a home run. They conferred and he decided they'd go take a look."
Reyburn then met with the other three umpires before the decision was made to go down in the tunnel and review the play on a television monitor near the visiting dugout.
"We decided to do it because it was so close," crew chief Tim Welke said, afterward. "We wanted to make sure we got it right."
After less than two minutes, Welke returned and signaled that the initial no-homer call was correct. Pence was awarded with an RBI double.
"It was quick," commented manager John Russell afterward. "It didn't delay the game too long."
After the game, Welke explained the timely and smooth-running process.
"The guards got out of the way and closed the door, and [plate umpire] Bill Welke and myself had privacy, and the technician had the three or four replays that we saw right away," the crew chief said. "What we saw looking at the replay was the same thing that we saw on the field, that the ball hit the ... yellow-coded part of the pad, and that just denotes the top of the fence. It's the same thing we had on the field, and the replay confirmed it."
This was the second time that replay has been used since its introduction on Aug. 28. Replay was used for the first time at Tropicana Field in a game on Sept. 4 between the Rays and the Yankees. In that game, replay upheld a home run by Alex Rodriguez that Tampa Bay contended had been just a long foul ball.
All televised MLB games are monitored and staffed by an expert technician and either an umpire supervisor or a former umpire at Major League Baseball Advanced Media headquarters in New York. A television monitor and a secure telephone link to MLB.com, placed next to the monitor, have been installed at all 30 ballparks.
If the crew chief determines that instant replay review is necessary on a particular disputed home run, he calls the MLB.com technician, who then transmits the most appropriate video footage to the crew chief and the umpire crew on site. The umpire supervisor or former umpire does not have direct communication with any of the umpires on site, and the decision to reverse a call is at the sole discretion of the crew chief. The standard used by the crew chief when reviewing a play is whether there is clear and convincing evidence that the umpire's decision on the field was incorrect and should be reversed. The use of replay is limited only to home runs: in or out, fair or foul, and fan interference.
Both managers and players from both clubhouses lauded the overall process afterward.
"Those guys are great at what they do and they got the call right," Pence said. "I was pretty grateful when I was out there that they wanted to make sure they got the call right. I was kind of indifferent on [instant replay] until a situation came up where it could change things, and now I think it's a great thing for baseball and I can't say enough about those guys."
Jenifer Langosch is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.