Matheny turned out to be right, and Beltran was, minutes later, credited with his 25th homer of the season, after the umpiring crew agreed to utilize instant replay in the second inning against the Brewers at Busch Stadium.
In question was where Beltran's blast off Brewers starter Mark Rogers hit off the right-field wall. There is a separation between the lower padded part -- which, if hit, is considered in play -- and the LED board above it. Balls that hit off the LED portion of the wall or the slab of concrete right next to it -- as Beltran's did -- are considered a home run.
Seeing the ball carom so hard off the wall was enough to convince Matheny that the ball hadn't hit the padded part.
"That's a great example of the rule changes, take a look at it," he said. "It's nice they got it right."
By having the initial call overturned, Beltran lost what would have been his second triple of the season. Not taking any chances about where the ball would strike the wall, Beltran hustled to third when he saw the ball carom off the wall and away from outfielder Nyjer Morgan.
Major League Baseball implemented replay to be used on home run calls in 2008. Beltran's home run tied Saturday's game at 1-1.
Jenifer Langosch is a reporter for MLB.com. Read her blog, By Gosh, It's Langosch, and follow her on Twitter @LangoschMLB. This story was not subject to the approval of Major League Baseball or its clubs.