Windhorst: Celtics 'Stomped Their Feet' over Perceived Al Horford Tampering

The Boston Celtics aren't over their breakup with Al Horford. 

According to ESPN's Brian Windhorst on his Hoop Collective podcast (h/t RealGM), the Celtics feel tampering altered their chances of negotiating a new contract with Horford, who signed with the Philadelphia 76ers: 

"I don't know if you heard this, but the Celtics were, from what I am told, one of the teams that kind of stomped their feet about what they felt was tampering. Not with Kyrie [Irving], although that looked like it was lined up pretty far in advance, but with Horford. 

"What happened with Horford, again from what I'm told, really upset the Celtics. They were thinking they were going to be able to negotiate with him. Talk to him about a new contract and, all of a sudden, it was like he already knew what his market was and he was out of there."

The 33-year-old center declined to exercise his $30.1 million option and became an unrestricted free agent. Reports indicated Horford became a free agent in order to renegotiate a deal and remain in Boston. However, ESPN's Adrian Wojnarowski relayed June 18 that Horford was "prepared" to seek a three- or four-year deal in free agency with another team.

And that is exactly what Horford did, agreeing to a four-year, $109 million deal (with $97 million guaranteed) with Philly shortly after free agency opened June 30.

Tampering is a hot-button issue in the NBA. Most recently, the New York Times' Marc Stein reported Monday that the Houston Rockets were fined $25,000 over the weekend after owner Tilman Fertitta commented publicly on the team's acquisition of Russell Westbrook before the trade was finalized officially. 

As it pertains to free agency, teams and free agents aren't allowed to begin negotiating until the window officially opens—this year, that was at 6 p.m. ET on June 30. Considering the number of deals that were reportedly agreed to either right at 6 p.m. ET or just after, it's hard to believe that discussions hadn't begun before then. 

"Obviously, if deals are being announced immediately after the discussion period begins, there had been prior discussions,” NBA Commissioner Adam Silver said earlier this month, according to Sports Illustrated. "I think the consensus at both our committee meetings and the board meeting was that we need to revisit and reset those rules, that some of the rules we have in place may not make sense. I think it’s pointless at the end of the day to have rules that we can’t enforce."

The league sent out a memo reminding teams of the anti-tampering policy in December following LeBron James' publicly talking about wanting to team up with then-New Orleans Pelicans forward Anthony Davis. 

It seems another reminder might be in order.