Miller racked up 36 saves while posting a 2.04 ERA last season. Hoch noted Miller hadn't been made aware of the decision:
Bryan Hoch @BryanHoch
Andrew Miller said he hasn't yet been told he will close during Chapman's suspension... will be ready for whatever the Yanks want.2016-3-2 13:34:08
The choice doesn't come as any surprise. Miller, a failed starter earlier in his career, has followed a similar path as Wade Davis of the Kansas City Royals to become one of the league's most dominant relievers over the past couple of years.
Garion Thorne of the Fantasy Sports Network highlighted the fantasy implications for Miller:
Garion Thorne @GarionThorne
Chapman due back May 9th vs. Royals. Have to figure Andrew Miller racks up 8-11 saves in meantime. That + 14.59 K/9 makes him Top 10 RP.2016-3-1 21:06:03
Dellin Betances was equally impressive in 2015 en route to a 1.50 ERA with an eye-popping 131 strikeouts in 84 innings. He should move back into the chief setup role while Chapman is out.
The suspension actually raises more long-term questions than short-term ones. Miller and Betances should fill the void just fine, but the uncertainty is what happens when Chapman is set to return after he was named the closer back in January.
If the Yankees' other relievers shine in his absence, does the team still force him directly into the ninth-inning slot anyway? If so, there will be a lot of pressure on him to succeed right out of the gate, or a controversy could begin to brew.
New York may be better off working him back into live action slowly—perhaps rotating the eighth inning with Betances at the outset—and ensuring he's back to his usual electric self before giving him the closer role back once the suspension ends.
That's a decision for early May, though. A lot will depend on how Miller and Betances perform in the meantime. If all three of them stay healthy and pitch up to their usual standards, it's hard to imagine there will be a more successful bullpen in 2016, regardless of who fills which role.