Backcourt edge keeping Celtics in front of Cavs

CLEVELAND — J.R. Smith reached out, placed his hands on Al Horford’s back and shoved the Celtics’ big man out of bounds.

It was the only time Smith was on target.

Smith’s shoddy performance in Game 2 — he missed all seven shots and committed a flagrant foul in 27 minutes — underscored a startling disparity between the starting backcourts that allowed the Celtics to withstand a 42-point effort by LeBron James and take a 2-0 lead over the Cavaliers in the Eastern Conference finals Tuesday night.

Smith and point guard George Hill were outscored 41-3 by the Celtics’ Jaylen Brown and Terry Rozier, who were faster, hungrier and maybe tougher.

“I don’t think tougher,” said Smith, who won’t be further punished for his aggressive foul on Horford. “They made shots; we missed shots at the end of the day. We had some good looks, but they didn’t fall.

“It’s a matter for us to bounce back, go home, try and (win) two, even the series up and come back here.”

Thanks to the NBA’s odd scheduling, Game 3 is not until Saturday night, giving Cavs coach Tyronn Lue plenty of time to consider tweaks to his starting lineup and rotations. After a 25point lambasting in the opener, Lue altered his frontcourt by putting Tristan Thompson with the first five and bringing Kyle Korver off the bench.

The moves worked as Thompson provided needed energy and Korver knocked down four 3-pointers and gave the Celtics’ defense more to worry about than just James.

Now Lue has to ponder another shake-up.

One option is to put Korver back at small forward, sit Hill and slide James to the point, where he typically plays anyway but where he’ll be more susceptible to double teams and will have to work harder than he is already.

Another possibility is to drop Smith, who is 2-for-16 from the field and missed all seven 3-pointers, from the starting lineup, but that would be risky because of his mercurial nature.

Lue is willing to live with Smith’s streakiness — he went 6-for-6 in Game 4 against the Raptors — but he can’t afford the defensive lapses that led to slow rotations and gave Rozier and others wide-open looks in Game 2. Smith has been locked in defensively throughout the postseason, so Lue is assuming he’ll get it together.

Lue’s decision not to play guard Jordan Clarkson for a single minute in Game 2 was curious, mostly because Clarkson is quick enough to handle Rozier and he scored 10 points in Game 1.

Veteran Jose Calderon appears out of consideration despite his steadiness and experience. Lue may fear the 36-year-old will be targeted and exposed defensively.