If a current American League contender such as the Tigers and/or White Sox pursue and eventually add Dempster, who has full no-trade veto power as a 10-year veteran having played at least five years for the Cubs, it would be the right-hander's first foray into the AL.
That change is not an easy one to make even for National League Cy Young winners, as Jake Peavy found out firsthand when moving from the Padres to the White Sox in 2009.
"There's no doubt this is a better league," Peavy said. "It's a different league, it's a deeper league. It's a tougher league to pitch in. I'll stand by those comments 100 percent. There's more money over here.
"It seems like the free agents end up over here. We took the two best players out of the NL last year and we got them over here this year. You don't get to face the same bottom of the order over here, so it's not what it is in the NL. That's not taking anything away from the NL. But as far as a pitcher, you have to work a little bit harder in this league. It's a well-known fact."
While the Dempster move was posed as a hypothetical situation to Peavy, the right-hander stands firmly behind the starting rotation the White Sox presently have in place. Peavy believes Chris Sale is "the best pitcher in the big leagues" leading the White Sox staff, and looks at a guy such as John Danks as the equivalent of a great midseason addition for the South Siders when he comes back healthy.
The addition of Dempster still would help any team, in Peavy's mind, even as an AL debut after 15 years in the NL.
"If you can pitch, you can pitch. I don't care what league it's in," Peavy said. "And Ryan Dempster can flat out pitch, if we are going to speak on Dempster.
"He will be just fine doing what he's doing now in the AL. That's all there is to it. Will you give up an extra run or two? Maybe. Will there be a few less strikeouts because you don't face the pitcher? Maybe.
"At the same time, pitching is pitching and I know that there are some guys who might have a tough time. But Ryan Dempster is a bona fide front-of-the-rotation starter when he's right. He can pitch anywhere."