Ben Simmons Philadelphia 76ers
Ben Simmons #25 of the Philadelphia 76ers flexes while the fans react to a dunk by Joel Embiid in the second quarter against the Boston Celtics during Game 3 of the Eastern Conference Second Round of the 2018 NBA Playoff at Wells Fargo Center on May 5, 2018 in Philadelphia. Mitchell Leff/Getty Images

If the Toronto Raptors or Philadelphia 76ers are going to reach the Eastern Conference Finals, they’ll have to make history. Both teams face seemingly insurmountable 3-0 deficits heading into Game 4 of their respective second-round series Monday night.

All 129 teams that have ever lost the first three games of an NBA playoff series have been eliminated in that round. Those odds mean a rematch between the Cleveland Cavaliers and Boston Celtics is likely inevitable.

Neither series was supposed to go this way. Faced with several key injuries, Boston was more than a 3/1 underdog to defeat Philadelphia when the series began. With home-court advantage after a 59-win regular season, Toronto was a 2/1 favorite to defeat Cleveland.

Just a week later, it’d be stunning to see either team make a comeback.

The betting odds suggest that the 76ers have the better chance of making history. They are +600 underdogs in the series, according to Sportsbook.ag, and the Celtics are -800 favorites. The Raptors have +1325 odds to win in seven games, while the Cavaliers are -6000 favorites.

Philadelphia is favored in Game 4 Monday night at Wells Fargo Center. They nearly took Game 3 at home when they had possession of the ball and led in the final seconds of overtime, but multiple mistakes by Ben Simmons allowed Boston to steal a win on the road.

The 76ers nearly took Game 2 in Boston, as well, blowing a 22-point lead.

It’s been a little different for the Raptors. Once Toronto lost Game 1 at home, it became clear that they were headed for another playoff disappointment against LeBron James and the Cavs.

Toronto gave away the series opener when they blew a double-digit fourth-quarter lead and couldn’t make a field goal in the final four minutes of regulation. James has just been too good since a poor Game 1 showing. He scored 43 points in a masterful Game 2 performance, as well as 38 points and a buzzer-beater in Game 3 to give Cleveland the win.

James owns the Raptors, going 29-1 in his last 30 home games against Toronto. The Raptors lost to the Cavs in six games in the 2016 Eastern Conference Finals before getting swept by Cleveland in last year’s conference semifinals.

Cleveland has far and away the best odds in the East to win the 2018 NBA Finals.