Celtics Finally Know What Illness Is Keeping Devin Carter Out originally appeared on NESN. Add NESN as a Preferred Source by clicking here.
Boston Celtics guard Devin Carter will be out for a while.
According to The Boston Globe's Gary Washburn, Carter has been diagnosed with mononucleosis and could miss "a few more weeks."
Mononucleosis is a viral illness that can cause extreme fatigue, fever and a sore throat.
Carter initially signed an Exhibit 10 contract with the Celtics, which the team later converted to a two-way deal.
Carter appeared in only one of Boston's four preseason games because of the illness. He made a strong impression in his debut against the Cleveland Cavaliers, scoring 17 points on 5-for-9 shooting in 25 minutes. He added five rebounds, three assists and two steals in the win.
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Carter can split his time between the Celtics and their G League affiliate, the Maine Celtics, this season. He is eligible to play up to 50 regular-season games with Boston while on a two-way contract.
The Sacramento Kings selected Carter with the No. 13 pick in the 2024 NBA Draft. The Kings traded him to the Atlanta Hawks in the offseason, but the Hawks waived him in September. He joins the Celtics with career averages of 6.4 points, 2.7 rebounds, 1.9 assists and 0.7 steals per game, shooting 40.1 percent from the field and 27.4 percent from 3-point range.
Carter is one of three players on Boston's roster on a two-way contract, joining Dillon Mitchell and Amari Williams.
Boston opens the 2026-27 NBA season on Tuesday, Oct. 20. The Maine Celtics open their regular season on Friday, Nov. 6.