Belichick spoke to Celtics ahead of Game 1

The Boston Celtics received a pep talk from New England Patriots head coach Bill Belichick ahead of the start of their first-round playoff series against the Philadelphia 76ers.

Celtics center Daniel Theis shared what Belichick told the team in an interview with NBC Sports Boston.

"Be prepared and control whatever you can control," Theis said. "Don't be surprised on the court when they run something, because you should know and be well prepared for it."

Belichick told WEEI's "Ordway, Merloni & Fauria" show Monday that he appreciated head coach Brad Stevens allowing him to speak to the Celtics.

"I was flattered that he asked and just tried to talk about playing at the time of year they're playing at," Belichick said. "Playoff basketball, playoff football - it's a little bit different. I don't know anything about basketball, but I know a little bit about competition and trying to perform well at the most critical time of the year, which is what they're in now. It was a great experience for me.

"I appreciate the opportunity from Coach Stevens and the Celtics and I wish them nothing but the best."

The Celtics took a 1-0 series lead Monday, defeating the Sixers 109-101. The teams will meet Wednesday in Game 2.