His fall from the rotation? A coach's decision, Arroyo said with a shrug. Crying in the locker room? No comment, he offered after a chuckle. Something to prove now? Not after nine years in the league, he suggested.
After Arroyo took a moment to talk about what an honor it was to put on a Celtics jersey, a reporter took one more stab, asking him if there wasn't at least a tiny part of him that wanted to crush the Heat for kicking him to the curb last month.
"I want to win a championship, to be honest with you," said Arroyo. "I want to win. I'm very passionate about the game and I have a great amount of respect for the game. I feel very fortunate to be here."
Maybe Arroyo simply isn't the vindictive type. Maybe the fact that the Heat have lost six of their last seven games since he last appeared on the court for them is enough revenge for being jettisoned in favor of Mike Bibby.
Or maybe he'd already been given a crash course in Boston's team-first, Ubuntu mentality. Maybe he'd been sold the Celtics' championship-or-bust mantra. Regardless, Arroyo said all the right things Tuesday, while heaping praise on his new home versus what he was a part of in South Beach.
"It's been a roller coaster," admitted Arroyo. "But I'm truly excited to start a new career here in Boston. It's a great opportunity for me and my career, to do whatever possible to help this team win. Whatever coach needs me to do out there -- be a leader, get guys involved, put them in the right spots. I'm just truly excited be part of a great franchise overall with great teammates."
Arroyo began the season as a celebrated piece alongside the free-agency assembled Miami Thrice of LeBron James, Dwyane Wade and Chris Bosh. Outside of American Airlines Arena in Miami, posters hung showcasing two players per banner. While James and Wade decorated one version, Bosh and Arroyo hung on another.
Arroyo started the first 42 games he appeared in for Miami before being dropped from the starting lineup in favor of Mario Chalmers on Jan. 22. The Heat won six of the seven games that Arroyo last appeared in off the bench, even briefly pulling ahead of Boston atop the Eastern Conference standings during that span.
But needing room to add Bibby, it was Arroyo that got cut free last month. When Celtics president of basketball operations Danny Ainge called last week to inquire about his interest in coming to Boston, Arroyo said it was a "no-brainer" and leaped at the opportunity to aid a different championship push.
Arroyo admitted Tuesday that he wasn't even certain what his role will be in Boston, but Celtics coach Doc Rivers suggested in recent days that the Green need a backup ball-handler to take some of the minutes off of Rajon Rondo.
From there, it's up to Arroyo to make the most of his time in Boston.
"It's nice [to have a pure backup point guard], it's just going to take him some time, but he knows how to run a team and that will be great for us," said Rivers. "We don't know [his playoff role] yet. We don't know how he's going to play. If he plays great the rest of the year, he'll answer that question."
Rivers said he thinks Arroyo will hit the ground running, and the player certainly looked comfortable on Tuesday, confidently guiding a second unit made up of a bunch of other fresh faces acquired over the last two weeks.
"That's the way we look at it: He's a point guard," said Rivers. "He's been a point guard all of his life. So I think some of the stuff he'll pick up pretty quickly. All the nuances, that'll take some time."
But unlike how it was with, say, Nate Robinson, added at last year's trade deadline, the Celtics seem confident that they can thrust Arroyo onto the floor and have him not be a liability. For his career, Arroyo is averaging 6.7 points, 3.1 assists and 1.7 rebounds per game. He averaged less than a turnover per contest for Miami this season, an encouraging number for someone whose No. 1 task will simply be valuing the ball and providing the second unit with a veteran quarterback.
Arroyo said he won't be overwhelmed by expectations put on him by the team or himself.
"At this point of my career, everybody knows what I'm capable of," he said. "Hopefully I can do a little bit more here and help this team. That's what I came here for. I'm excited to get things going and hopefully win a championship in Boston."
He's immersed himself in film study to help him learn the playbook. Like any good point guard, his focus is clearly on what's ahead and not what's behind.
Asked about his fall from grace in Miami, Arroyo admitted he didn't quite understand coach Erik Spoelstra's decision, but said, "That's a coach's decision. My job was really to stay ready. It was not about me or anybody else, just the team. I'm a true professional when it comes to that."
He proved it Tuesday, stressing that winning a title is his top priority, and that playoff path doesn't even have to wind through South Beach.
"I would love to win a championship, no matter who we beat," said Arroyo. "I think this is the right team, the right guys to do it. I love the chemistry they have on the court and off the court, the team they have. It's what everyone would like to have."
Arroyo said the first thing he did as he prepared to latch on with the Celtics is phone Jermaine O'Neal, someone he played with last season in Miami.
"The first thing I did was call Jermaine, just to get his side of how this team works," said Arroyo. "He told me this is by far the best team he's been a part of. I'm looking forward to having the same experience."
Arroyo enjoyed a similar experience on a veteran Detroit squad in 2005, where he was a late-season addition via trade. That team marched to the NBA Finals before losing to the San Antonio Spurs. Now he has a second chance at a crown with a team that believes it can win it all this year.
And if that happens, he'll look back with nothing but appreciation for the Heat allowing him to join a real championship team.
Chris Forsberg covers the Celtics for ESPNBoston.com.