Aroldis Chapman

CINCINNATI -- Jay Bruce and Drew Stubbs couldn't agree what pitch Aroldis Chapman got Jose Reyes swinging at to strike out, ending the eighth inning of Cincinnati's 4-0 opening-day victory, but they both said they were glad they didn't have to face it.

Bruce thought the pitch was a split-finger fastball and called it "unhittable," while Stubbs thought it was a slider and "unfair."

Chapman and catcher Ryan Hanigan said the 1-2 pitch was a slider -- and Reyes swung through it awkwardly to end Chapman's perfect eighth inning. And then, as Chapman walked off the field, Reyes said something to left-hander and the pitcher laughed. Reyes' opinion was probably close to Bruce's and Stubbs'.

You can watch it here.

What's more impressive, was as bad as Reyes' swing looked, the ball, according to Pitch F/X, was just barely off the center of the plate. Of course, a 90-mph slider, no matter where it's thrown, is tough to hit.

"He got on top of it, it's got good action -- and sometimes it'll back up a bit, but as long as it's got depth, it's good," catcher Ryan Hanigan said. "It went down, but didn't come in. That'll happen with sliders sometimes, they'll go straight down. As long as it's got depth, that's what I want. I don't care if it comes in, especially against a righty. You could see Reyes was cheating fastball the whole way. I could tell he was going to do that."

Chapman didn't hit triple-digits on the radar gun readings, but he doesn't have to if his slider is working. According to Pitch F/X, his top speed was 97.5 mph, but his fastball averaged 95.92 mph. And the slider, it came in hot, too. Pretty much any batter's going to be looking fastball, Reyes included.

"You don't have to (sit fastball), but you could tell he was going to," Hanigan said. "We hadn't thrown a slider yet and he was late on the one before. Guys in this league aren't going to be late too many times. And when you saw him be late, my thought process was he's going to try to crank it up and try and get the ball out and we're going to do this. The bottom line is it was down and in the zone on a two-strike count and that's all you want."

Chapman worked in the rotation most of spring and is currently the team's top set-up man, but pitching coach Bryan Price said Tuesday that the team hopes to get him back to starting sometime soon. The problem is, he may need some work in the minors, and right now he looks just so good at getting big-league hitters out. Facing Reyes, catcher John Buck and pinch-hitter Austin Kearns, Chapman threw 10 pitches, seven for strikes and got two strikeouts.

WIth closer Ryan Madson out for the year, lefty Sean Marshall sliding into the closer's role and another lefty, Bill Bray, not ready to serve in the late innings, Chapman will be coming out of the bullpen -- and that may be something of a blessing for opposing teams.

"That was a great eighth inning," Reds manager Dusty Baker said. "Sure, Aroldis is eventually going to start, but with our bullpen the way it is right now, he is the best man for the job right now."