Brad Stevens’ reliable options shrunk and rotations expanded deeper into this road trip. Starting three bigs turned into 30 Carsen Edwards minutes against the Clippers. Grant Williams emerged deep off the bench to close a game Daniel Theis and Tristan Thompson started against the Warriors. Stevens goes off feel as much as numbers. What he sees in practice and short stints during games matters. “Garbage time” is as valuable as other sequences, and he’s seen Edwards improve since he returned from COVID-19 to play in scrimmages with Tatum and Boston’s coaches at Auerbach Center to get back in shape after their three-week layoffs. Edwards played so well in them that the Celtics pulled him and made him a shoo-in for minutes in recent weeks. Edwards scored 16 points on 5-of-8 shooting in Boston’s upset over the Clippers, so on Sunday he started for the first time in the NBA. It didn’t last long. Devin Booker looked for the small guards on five straight possessions and the Suns scored on each. Phoenix started the night hitting 8-of-10 within the restricted area as a struggling C’s defense got peppered by the Suns’ perimeter players with jumpers and finishes inside. Mikal Bridges started 4-of-5, Booker hit 5-of-8 in the first half and dished five assists to teammates. He finished with 18 points and a critical shot with 43 seconds left that halted Boston’s comeback to within three points in the final minute. Phoenix won 100-91. Nick Gelso, Josue Pavon, Jimmy Toscano and Bobby Manning talked about the Celtics loss and Brad Stevens as Boston fell to 12-10.