Brad Stevens, speaking prior to the Celtics game against the Dallas Mavericks, said that Hayward had underwent surgery beginning at 5 p.m. ET in New York and the team was preparing to provide an update following surgery.
While the timetable is yet to be determined for how long Hayward will be out, he's likely to miss at least a month of action.
And while the timing certainly isn't great when you consider how both Hayward and the Celtics were playing, Stevens reiterated that this injury is dramatically different than the ankle injury Hayward suffered a couple years ago which sidelined for all but the first five minutes of the 2017-2018 season.
This injury isn't that severe, even with the most conservative timelines having him back on the floor at some point this season.
But the Celtics did get some good news on the health front with Enes Kanter (knee) available to play for the first time since the team's season-opener at Philadelphia.
Kanter's return comes at a good time for Boston which will look through a multitude of bodies at Dallas' 7-foot-2 center Kristaps Porzingis who comes into tonight's game averaging 20.1 points, 8.3 rebounds and a career-high 2.6 blocked shots per game while shooting 39.5 percent from 3-point range.
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Celtics awaiting Hayward update; Enes Kanter (knee) set to return originally appeared on NBC Sports Boston