"It's official now," he said, "I'm soon to be a Celtic."
At the age of 37, the 14-year veteran is averaging just 3.7 ppg this season, by far the lowest total of his career.
His presence will still be felt in the locker room nonetheless.
Finley has been doing it a long time and his 111 postseason appearances will provide the Celtics with yet another strong veteran presence to lead the team down the stretch.
His role is not expected to be significant on the court, though. Finley will be playing behind Paul Piece and Marquis Daniels, but will serve as a solid injury insurance in the event either guy goes down.
As a career 31.7 percent three-point shooter, he should also help to bolster the Celtics long-range game. After recently trading away Eddie House, Boston has struggled a bit in that category.
When the playoffs come rolling into town, that's when Finley's contribution will be truly recognized. Don't understate the importance of veteran leadership when the gloves come off.
Playoff basketball is an entirely different game and guys that been there before help the rest of the roster handle the change.
For his career, Finley is averaging 13.6 points and four rebounds in postseason play. Last season, he averaged eight points and three rebounds in five playoff games with the Spurs.
It's not out of the realm of possibility to expect similar production this time around. He's the type of player who steps up for big games.
The Celtics playoff run will pack a stronger punch now that Finley's on board.