Philadelphia 76ers All-Star center Joel Embiid wasn't his best in Game 4 against the Toronto Raptors on Sunday afternoon. Embiid finished with just 11 points on 2-for-7 shooting from the floor, along with eight rebounds and seven assists as he looked far from his usual dominant self. The Raptors would go on to win 101-96.

As it turns out, Embiid was battling an illness that prohibited him from sleeping, required IV fluids at 6 a.m. and left him unsure if he would even be able to play at all. 

"I got a text from him at 6:20 a.m. this morning telling me he didn't sleep all night, he really never felt this poorly and he was unsure if [he was] going to play," Sixers head coach Brett Brown said after Game 4. "'I want to give you a heads up. I'll try, but I don't know.' With that, started my day … to his complete credit, he just kind of willed his way through it.

"All during pregame film, you can hear him sneezing and sneezing and sneezing. You try to ignore it and coach through and show the players pregame tape, but I'd be lying if I were to tell you it wasn't completely on my mind as I'm talking to the team and showing the tape, listening and seeing him."  

Embiid ultimately felt good enough to play, but he was unable to produce at the level that the Sixers have come to expect from their big man. As a result, the Raptors were able to even up the series at two games apiece. Afterward, Embiid shouldered the bulk of the blame for Philadelphia's Game 4 loss. 

"I mean, at the end of the day, it's on me," Embiid said. "I got to be more aggressive. Today wasn't the same as [Game 3]. Staying aggressive, especially offensively, I've got to help my teammates better. But still on me ... I'm just not myself." 

Moving forward, beginning with Game 5 (8 p.m. ET -- watch on fuboTV), Embiid knows that if he steps out on the court, the Sixers need him to be more aggressive if they want to have a chance to advance past the Raptors.

"It doesn't matter. Once I step on the court, I got to do a better job," Embiid said. "No matter the situation I just need to be aggressive."

When Embiid is at his best, he is downright dominant. When he's hobbled, however, the Sixers become very vulnerable. Thus, his health will be something major to monitor as the series between the 76ers and Raptors progresses.