Joel Embiid, Brett Brown Remain Optimistic Heading Into Game 4

Staying positive is hard when your team falls three games behind in a playoff series. Despite defeating the Boston Celtics three out of four times this season, the Philadelphia 76ers knew they were still heading into a tough series as they came into the first round of the playoffs as the sixth-seeded underdogs.

Looking at the scoreboard, you can tell exactly why the Sixers aren't the favorites in this series. Although the Sixers kept it interesting in two out of three games in the first round of the postseason, Boston has had no issue closing games out with a convincing victory. Now, heading into Game 4 on Sunday, the Sixers are officially in a do-or-die situation as it's win or go home for them.

"It sucks, but you can't give up," said Sixers starting center Joel Embiid after Game 3. While the odds of teams coming back from an 0-3 deficit in the playoffs certainly aren't in the Sixers' favor, Embiid and 76ers head coach Brett Brown made it clear that Philly isn't throwing in the towel just yet.

"I'm not rolling over," stated Brown after the Game 3 loss. "Everybody would assume that the series is over because we're out 3-0. We're going to come in to play the game and get a win. To dust it off like it's delivered for pride purposes, of course, but it's to keep the series alive. I truly mean that. That's my message to them (the players), and that's my message to my staff."

Whether the 76ers genuinely believe they have it in them to beat the odds and come back is unclear -- but one thing is for sure -- the 76ers do not want to be the first team sent home this week by way of a sweep against their rivals. "I don't want to be swept -- I don't want that in my resume," Embiid said. "You have to keep fighting and play hard. I've been playing my butt off, and I'm going to come in and do everything that I can to make sure we win a game and take it one game at a time."

The Sixers and the Celtics will tip-off Game 4 on Sunday afternoon.

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