Consider Sunday one of his biggest ups.
Miller was added to the lineup for Game 5 of the Rangers' Eastern Conference First Round series against the Philadelphia Flyers, his first Stanley Cup Playoff game, and he responded with an assist, a plus-2 rating and one shot on goal in 10:22 of ice time.
The Rangers won 4-2 to take a 3-2 lead in the best-of-7 series. Game 6 will be Tuesday in Philadelphia. Game 7, if necessary, will be Wednesday in New York.
Sunday was Miller's first NHL game since March 28. The 2011 first-round pick (No. 15) had three goals and three assists in 30 NHL regular-season games, but spent the majority of the season with the Rangers' American Hockey League team, the Hartford Wolf Pack.
He had been called up from the AHL six times but never stuck. And when he was returned to the AHL on April 2, coach Alain Vigneault publicly questioned Miller's commitment to being a full-time NHL player.
"Until there is [more commitment], he just hasn't earned the right to be at this level on a regular basis," Vigneault said.
Rather than sulk, Miller worked to earn his way back into the lineup. And after being scratched in the first four games against the Flyers, he found his name listed on the active roster for Game 5.
"I was told I'd have a chance [Saturday], so I just came to the rink at 9:30 [Sunday] and saw my number on the board," Miller said. "It was a pretty special moment."
Miller replaced Daniel Carcillo at right wing on a line with center Brad Richards and left wing Carl Hagelin. Richards, a veteran of 97 playoff games, said he did his best to make sure Miller was calm and focused, and said he was happy to see his linemate have a solid playoff debut.
"He was good," Richards said. "He was on the puck right from the first shift. He's not scared to make a play or hold onto pucks. Just have to channel that the right way and he did that [in Game 5]. You have to know when it's time to try some of those things and when it's time to fight another day. [Sunday] he did all that. When it was time to chip pucks in he did that. And he held on to pucks and battled and got to the net. We got a big goal out of it."
Miller drew an assist on Richards' goal. He was set up for a shot off a 4-on-2 rush but missed the net. Hagelin got the rebound but Flyers goalie Steve Mason stopped his wraparound attempt, and then denied Miller from right in front. That shot bounced off Mason and went to Richards, who scored from the left side to make it 2-0 at 8:07 of the second period.
Vigneault said Miller supplied exactly what he was hoping for when he made the lineup change.
"I thought he played well," Vigneault said. "He brought us some good skill level, did some good plays. Just thinking that he might be able to help us out and I thought he did a good job. ... [Carcillo] brings a lot of good things; the energy, the physically. J.T. brings a higher skill level, protects the puck a little bit better. I thought [Sunday] that would help us out."
Miller said there's no feeling of vindication on his part. He's just happy to be playing at the most exciting time of the year.
"Just feels great to have another chance," Miller said. "I'm excited coming out of the game. ... It was an awesome experience."