The Philadelphia 76ers opened up the 2021 NBA Preseason while shorthanded. As expected, the Sixers didn't have their starting point guard Ben Simmons on the floor as his holdout continued. In addition to Simmons, rookie center Charles Bassey also wasn't on the floor as he was working on finalizing his work visa.

Last but certainly not least, the Sixers were missing two key starters in Joel Embiid and Tobias Harris. Although both players were with the team on Monday night in Toronto, they both sat out for different reasons.

Embiid got the night off. After participating in every practice since training camp started, the Sixers gave the big man some much-needed rest. After all, he is coming off of a playoff run where he tore his meniscus. Therefore, the Sixers are going to make sure they take it easy with Embiid this offseason, so he makes it to the regular-season opener healthy.

As for Tobias Harris, he was dealing with knee soreness. According to Keith Pompey of The Philadelphia Inquirer, Harris was kneed in the knee during a workout. The good news was his setback was nothing serious -- the Sixers just wanted to be cautious and didn't want to risk further injury.

Could Embiid and Harris be back on the floor for Thursday's preseason rematch against Toronto? 76ers head coach Doc Rivers doesn't rule it out. "Most likely, but we went pretty hard today," he revealed. "So, we always wait until tomorrow."

Harris and Embiid were back out on the floor for practice on Wednesday afternoon. As expected, their reasons for sitting out on Monday weren't anything that would keep them off the court for too long. As the Sixers are set to tip-off against the Raptors on Thursday night once again, Embiid and Harris were left off the injury report on Wednesday. 

Justin Grasso covers the Philadelphia 76ers for Sports Illustrated. You can follow him for live updates on Twitter: @JGrasso_.