SALT LAKE CITY (AP) — Danny Ainge sat with a look of satisfaction Wednesday as he watched Boston play the San Antonio Spurs in summer league action. It's been quite a week for the Celtics president of basketball operations.

The franchise came to an agreement with Gordon Hayward on a four-year, $128 million deal on Tuesday. Ainge also watched rookie Jayson Tatum, the No. 3 overall pick, shine in his first two professional games at the Utah Jazz Summer League.

Fans heckled Ainge throughout the game, but nothing seemed to bother him or coach Brad Stevens.

Tatum put on a show again, with 23 points, 10 rebounds, two assists and one steal in 31 minutes. The rookie showed a bit of everything on offense, including a tip-dunk that had the crowd gasping.

"He's going to be a pretty good player in this league for a long time," Celtics summer league coach Jerome Allen said. "As the games progress, I think I'm beyond feeling surprise by what he's able to do on the floor, from a number of different spots on the floor. It's good to see solid production out of him."

The Spurs won 81-70, but Tatum's performance was most important to Celtics fans. He hit the go-ahead jumper on Monday with 5.7 seconds remaining.

"I'm just trying to be well-rounded," Tatum said. "There's effort in diving to the floor and rebounding. It doesn't take skill to do those things. I'm just giving that extra effort to help the team."

Bryn Forbes paced the Spurs with a game-high 31 points, including a 6-for-8 effort from behind the arc. Dejounte Murray struggled with five points on 0-for-10 shooting.

A look at the day in summer league:

MOVING ON

Jazz general manager Dennis Lindsey spoke with the media Wednesday for the first time since Hayward made his announcement. Lindsey said he hasn't spoken with Hayward, but the two have texted back and forth. Lindsey said after the season the organization had contingency plans in case Hayward left. He said Wednesday that the timing of the decision is problematic for those plans. Most of the marquee free agents have made their decision by now and the Jazz are losing 21.9 points, 5.4 rebounds and 3.5 assists per game.

DANTE DAZZLES

Jazz point guard Dante Exum is the only lottery pick from the 2014 and 2015 drafts playing in the Salt Lake City and Orlando sessions. Utah's coaching staff expects the 2014 No. 5 overall pick to dominate, and he did so Wednesday.

Exum finished with 26 points, 10 assists and five rebounds. He shot 9 for 16 from the field, including three 3-pointers, in Utah's 100-94 win over Philadelphia.

"Just getting to the paint and finding guys," Exum said. "I'm trying to learn a lot about where guys like to get the ball. I think that's part of my development, where I need to learn to put guys in good situations.