Chapman has owned the eighth inning for the Cincinnati Reds this season, pitching so dominantly as a setup man that there is bound to be speculation about him taking over the ninth. This is not to mention the widespread opinion that his long-term future will be as a starting pitcher.
The question came up again Saturday at Yankee Stadium. The circumstances of the Reds' 6-5 Interleague victory over the New York Yankees made it a mandatory topic of discussion.
Working with a 6-3 lead in the eighth, Chapman dealt with three of the Yankees' best in overpowering fashion. Chapman struck out Curtis Granderson with a 99-mph fastball. Then he stuck out Robinson Cano with a 99-mph fastball. Then he got Alex Rodriguez to pop to short on a 98-mph fastball. It was a small sample size, but it was domination in the home of the Bronx Bombers.
Sean Marshall, the Reds closer since Ryan Madson was lost to Tommy John surgery, took over for the ninth and gave up hits to four of the five batters he faced. With one out, the score 6-5 and the tying and winning runs on base, Red manager Dusty Baker summoned Jose Arredondo. This would be Arredondo's first save, as he got the two ground balls that the situation absolutely required from Derek Jeter and Granderson. And the Reds got to breathe a sigh of relief.
The juxtaposition of Chapman's dominant inning with Marshall's work was inescapable. These performances once again opened the door for questions about Chapman's role, but this time in the short-term future. Baker acknowledged that he had spoken to Chapman about the possibility of shifting into the closer's role, although he said no decision had been reached.
"He's been so good in the eighth, but like I've said, you've got to graduate to that position [closer]," Baker said. "Who knows, maybe graduation time is here.
"We've had discussions, we've talked about it. Matter of fact, I already talked to him [Chapman] about it a little while ago. We'll see.
"Marshall's a team man. You know this [closing] is not what he signed up for. It's what he was forced to do. He signed up to be a setup man in the eighth and then we'd go to Madson. And Chapman was going to be in the rotation. Then [Nick] Masset and Madson, everybody got hurt, and we had to revamp and come up with Plan B. So we'll see about Plan C."
Chapman said, through interpreter Tomas Vera, Reds assistant athletic trainer, that he and Baker had spoken about the possibility of Chapman becoming a closer. But he also stressed that no decision had been reached.
"The conversation we had was how I would feel about being a closer," Chapman said. "I said, 'I feel good, I feel great, whatever way you guys want to use me.' But in the conversation there was nothing affirmed about what was going to happen. It was just a conversation of what I would think about it. Nothing official."
Chapman has captured the imagination of not only Reds fans but of any baseball fan who has glimpsed his work. There isn't anybody else capable of throwing 105 mph, and even beyond that, the 24-year-old left-hander has the kind of potential that is seemingly limitless. Marshall, who was highly successful in a setup role for the Cubs, was thrust into the closer's role when Madson was injured.
Chapman's work this season is on the verge of redefining the term "dominant." In 17 appearances covering 21 1/3 innings, he has given up one run, and that was unearned. He has allowed only seven hits -- six of them singles -- walked seven and struck out 38.
It seems that he is inevitably headed toward the closer's spot, although Baker points out that Chapman's conversion to a relief role was relatively recent and he is still learning the relief ropes.
Chapman's kind of talent lends itself to a central question: He has the potential to be an immense success, but what job will he be doing while he is achieving that success?
"Everybody asks me that question," Baker said. "Some want him to close, some want him to start. But there's only one Chapman. I can only put him in one of those [roles]."
Long term, Chapman probably will be in the Reds rotation. This is Baker's view and the organizational view. But that isn't the issue for the Reds now. Chapman has been invaluable for the Reds this season. "Without him, man, we wouldn't be close," Baker said.
Aroldis Chapman -- the eighth inning or the ninth? There is only one of him. On the mound, that appears to be his only shortcoming.
Mike Bauman is a national columnist for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.