The Celtics have won seven of their last eight games to surge into a tie for third place in the Eastern Conference. They have an All-Star, they have a regular rotation, and they have plenty of confidence.

Although the current run has been impressive and important, it has not included any wins against the league’s six elite teams — those with winning percentages of .650 or higher. But on Friday the Celtics will have a chance to change that as they go on the road to face LeBron James and the Cavaliers.

Cleveland began this season as the heavy favorite to win the East, and despite injuries and a stunning in-season coaching change, that outlook has not shifted. The Cavaliers are still expected to make the Finals, and aside from perhaps the Raptors, there have been few East teams that have sustained strong play long enough to be considered threats.

It can be misguided to put too much stake in a regular-season game, but for the Celtics this matchup does feel like a litmus test, a chance to assess their progress.

“They’re the top of the East right now,’’ said Celtics forward Jae Crowder. “So every time you get to see the top team of the East, you try to gauge and see where you’re at. So we’re definitely looking forward to it.’’

This will be the Celtics’ first trip to Cleveland since Game 2 of last season’s first-round playoff matchup. Boston garnered some respect around the league for its competitive play in that series, but ultimately it was swept in four games. On Friday there certainly will be no satisfaction in simply being a plucky opponent.

“We’ve got to go in there and try to handle business,’’ Celtics guard Isaiah Thomas said. “It’s going to be probably a hostile environment.

“They’re a great team, but we’re not going to back down from anybody. We’re going to try and play our game and get out and run and get easy baskets, and hopefully we can get a win.’’

The Celtics and Cavaliers have met just once this season, with Cleveland taking an 89-77 win at TD Garden Dec. 15. Both teams have undergone extensive alterations since then, however.

At the time of the first meeting, Cavaliers point guard Kyrie Irving was still out with a knee injury and David Blatt was still the coach. Now, of course, Irving is back and Blatt has been fired, replaced by former Celtics assistant Tyronn Lue.

The Celtics, meanwhile, were without injured guard Marcus Smart in December. After a disastrous stretch, Smart has been the Celtics’ top 3-point shooter over the last seven games, going 17 for 37 (45.9 percent).

Also in that December game, David Lee played 18 minutes and James Young 16 for Boston. Both players now are out of the regular rotation. The Celtics have finally established more consistent groupings, and the results have been noticeable. Now they will be tested.

“We’ve just got to come with it,’’ Celtics guard Evan Turner said. “[Cleveland’s] defense has been really great versus us where we struggle. Obviously, the offensive rebounding, and we’ve just got to be clicking.

“I think, first game we played them this year, our offense wasn’t too great and they got going and they hit some shots. We have to make them uncomfortable and we have to be clicking and our pace has to be great.’’

Cleveland is coming off a surprising loss to the Hornets in Charlotte Wednesday, but has mostly been impenetrable at home, going 19-3. If the Celtics win this game, optimism and expectations and hope will swell considerably. But even a loss could help, giving them a better vision of how they must improve over the next few months.

“One of the best teams in the NBA,’’ Celtics coach Brad Stevens said. “I haven’t seen them a lot since our game, but they handled us here. And obviously they have a few of the better players in the NBA. So it’s going to be a heck of a challenge.’’

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Lee, who was a reserve on the Warriors’ NBA title team last season, joined his former team when it was honored at the White House Thursday afternoon. He is expected to be back with the Celtics in time for Friday’s game.

Adam Himmelsbach can be reached at adam.himmelsbach@globe.com. Follow him on Twitter @adamhimmelsbach.