The Boston Celtics will be shorthanded when the Eastern Conference Finals tip off tonight in Miami. Starting center Al Horford tested positive for COVID and entered health and safety protocols, plus the Celtics upgraded point guard Marcus Smart from questionable to out for Game 1 versus the Miami Heat.

Al Horford (42) and Marcus Smart (36) will not play for the Boston Celtics in Game 1 against the Miami Heat at the start of the Eastern Conference Finals. (Image: Winslow Townson/USA Today Sports)

Oddsmakers opened Game 1 with the Heat installed as a -2 favorite. After news broke about Horford and Smart being out for Game 1, the line jumped -4.5 in most spots, but there are a couple offshore books at -5.

DraftKings also altered their series markets to reflect the absence of Horford and Smart in Game 1. The Celtics were -185 odds to win the series this morning, but they since slipped to -135. The Heat were +190 underdogs to win the series, but saw their odds bump to +130.

Smart Out, Horford in Quarantine

The Celtics prepared for the possibility that Smart would not play in Game 1. Smart suffered a foot sprain in game 7 of the Eastern Conference Semifinals when he collided with Giannis ‘Greek Freak’ Antetokounmpo. An MRI on Monday revealed a right foot sprain and Smart was listed as questionable. He did not respond well to treatments, so the Celtics decided to keep Smart out of the lineup in Game 1. Derrick White is expected to start in place of Smart.

Horford played a pivotal role in a Game 4 come-from-behind victory when he led the Celtics with 30 points, including a 16 points in the fourth quarter without missing a shot.

In 11 playoff games, Horford averaged 13 points and 9.4 rebounds per game. Without Horford in the line up, Robert Williams III should get the start. Williams missed a the last four games of the Bucks’ series with a bone bruise after he also suffered a collision with Greek Freak.

“Rob is available,” said head coach Ime Udoka. “He’d be on a needed basis with no minutes restriction. I’m cautious with guys coming off a layoff without touching the court, but it’s a little bit different starting a new series as opposed to being injected into a Game 7 or whatever the case was before. But he’s available, looking better every day, and getting more confident in that.”

Horford testing positive for COVID-19 was highly unexpected. The main concern is there’s not an simmering outbreak within the locker room, and the Celtics hope that Horford is an isolated incident. Horford entered health and safety protocols for a third time, which included the preseason and a second time in December.

Check out more coverage of the 2022 NBA Playoffs.