By Michael Hurley, CBS Boston

BOSTON (CBS) — The Boston Celtics are 9-0 on their home court this postseason. After their 30-point loss in Cleveland on Saturday, they’re now 1-5 outside of their home building.

Clearly, the Celtics are a different team when they leave the TD Garden. But Celtics head coach Brad Stevens cannot look at those disparate records and conclude that the location of the game has anything to do with the results on the court.

“Well to be honest with you, in my 11 years as a head coach, I probably haven’t talked about road and home five times with our team. It’s about how you play between the lines,” Stevens said after the Cavaliers won 116-86 in Game 3 to cut Boston’s lead to 2-1 in the Eastern Conference finals. “Because I think if you start talking about that, then you find excuses in both places. And we can’t play like we played tonight, no matter where we play. If we would’ve played in Boston like that, we would’ve gotten beat.”

That last part is most certainly accurate, but the perplexing part of these Celtics is why they’ve struggled so much on the road. The divergence in performances has been staggering. In their nine home wins, the Celtics have won by an average of 11.3 points. In their six road games, they’ve been outscored by an average of … 11.2 points.

They have been, essentially, two different teams this postseason. As a result, they’ve welcomed the Cavaliers back into this series.

Stevens remained at a loss for an explanation.

“Well we were great in the regular season on the road. We were one of the better teams in the regular season. I don’t have an answer for you in the playoffs,” Stevens said. “But all of that is a moot point for us. We have to play well. We have to focus on us and play well and play with more substance. And [the Cavaliers], again, they took it to us. When you get in the playoffs, you get in these environments — not only are you playing in great environments, you’re playing really good teams. When we’ve gone on the road, we’ve gone on with 2-0 leads in all three series. And two of those three times we didn’t play as well as the other team. Point blank. They just outplayed us.”

How the Celtics respond to their biggest road flop of the postseason will go a long way to influence this series. If LeBron James and the Cavs are able to tie the series with another convincing win in Cleveland, the atmosphere will be tense when the Celtics return to their home floor for Game 5.

“The valuable lesson is that Cleveland outplayed us,” Stevens said. “And we’ve got a game on Monday and we’ve got to be ready to play better.”