PHOENIX -- Kevin Durant isn't ready yet for the curtain to lift on his debut with the Phoenix Suns, but the preparation got serious Thursday as he entered the final stages of his return from a knee injury.

Durant took part in all of a two-hour intense workout and scrimmage in the team's first official gathering after the All-Star break. The Suns brought in referees to make it a gamelike atmosphere, and coach Monty Williams said it was the longest and most intense workout the Suns have had since training camp.

Afterward, the Suns ruled Durant out for Friday's home game with the Oklahoma City Thunder. He's officially day-to-day but is expected to make his return during the team's upcoming four-game road trip. Sunday's game in Milwaukee is a possibility, but as Durant works on improving his conditioning in his first contact workouts following a right MCL sprain suffered on Jan. 8, Wednesday in Charlotte is a more likely return date.

But Thursday there was a new energy within the team as Durant played 5-on-5 with his new teammates for the first time.

"When guys watch him work, I think it's something that inspires people to get after it in their own workouts," Williams said. "Because they're not going to find anybody that goes as hard as Kevin. When he's doing his individual stuff it's amazing to watch."

During the All-Star break, Durant worked out at the Suns' facility with teammates, including Devin Booker. The two played several one-on-one games, though Booker firmly refused to announce who came out the winner.

"It was hard to put into words, I can't wait until we do it against other teams," said Booker, whose arms were scratched up, illustrating the intenseness of the workout. "A lot of teams have one good defender or two good defenders, now you have to find who you're going to put them on."

Durant's work ethic is already making an impact on the team. Players have noticed he comes early and stays late.

"I think everybody's competitive level has risen a little bit," center Deandre Ayton said. "The atmosphere around the facility has, I won't say gotten intense, but it's definitely a little denser when it comes to business. Ain't no more playing games or, you know, less smiles, more seriousness and getting a job done."