Gordon Hayward and Kemba Walker, reunited in Boston.

No, the two NBA stars never took the court together on the same squad. But in welcoming Walker to the Boston Celtics on Twitter, Hayward made a "Throwback Thursday" reference to their time as teammates.

So, what's he getting at?

This seems to be Hayward's sly nod to July 10, 2014 (almost exactly five years ago), when he agreed to a four-year, $63 million offer sheet with the Charlotte Hornets in restricted free agency.

That would have made him teammates with Walker, then entering his fourth season in Charlotte. But the Utah Jazz matched the Hornets' offer two days later, re-signing Hayward to a four-year deal and ending his two-day stint as a "member" of the Hornets.

(Walker's UConn Huskies did beat Hayward's alma mater, Butler, in the 2011 NCAA title game, but Hayward's Bulldogs tenure ended in 2010.)

But Hayward and Walker now can call each other real teammates, and as the two maximum-contract players on Boston's roster, both will be crucial to the success of a Celtics team in transition after losing Kyrie Irving and Al Horford.

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