ATLANTA >> The head coach, alien to the NBA, was hired last summer by a callow team with prospects modest enough to allow for a grace period. Instead, Dave Blatt is expected to win big, and now.

The megastar free agent acquired after Blatt’s arrival has seemed, to some observers, disconnected from the coach and ebbing physically as he crosses into the uncertainty of middle age. On Tuesday, the night of his 30th birthday, LeBron James bypassed the game against the Atlanta Hawks to rest a sporadically sore left knee.

The other All-Star catch in free agency has personified the team’s defensive deficiencies, which hardly presage a playoff run. That All-Star, the prolific scorer Kevin Love, was withheld for the entire fourth quarter of a tight game last week because he was judged incapable of guarding any opposing player in a downsized lineup.

The Cavaliers faded to 18-13 with a 109-101 loss to the Hawks, who were absent their own most decorated player, the All-Star Al Horford, who surrendered to nausea after suiting up.

Blatt was jocular before tipoff Tuesday, even having just elected to hold out James, who was categorized as day to day. That makes James questionable for Wednesday’s home date with Milwaukee.

An aching left knee also kept James idled during a Dec. 11 game, but the latest ailment was attributed to a collision with courtside seats in Miami on Dec. 25. James participated in the morning shoot-around with every intention to play.

While James is widely perceived as forever young, he is nearing the midpoint of his 12th season. His statistical line this season would draw envy from any peer; nobody has a superior combination of points, rebounds and assists.

Subtle decline in physical capacity is in the eye of the beholder, and some James watchers sense that he must rely more on cunning and brainpower, less on running and leaping.

Blatt calmly scoffed at media accounts from Monday that said he and James were operating on separate wavelengths and that he had been unable to connect sufficiently with the team.

"That’s simply not the case," Blatt said, adding of such perceptions, "Just because they are reported doesn’t make them true."

He went on to say: "We have a very good group. Close-knit. The guys are engaged and listening."

Blatt acknowledged distress over some defeats, most recently one Sunday against feeble Detroit, by 23 points, and another two weeks ago against the Hawks, by 29, both at home. The margin in six losses was in double digits, a damning statistic for an overwhelming Eastern Conference favorite that today stands in fifth place.

"We are looking to get back our consistency and competitiveness," said Blatt, who drew encouragement on the latter goal from the defeat.

"We didn’t win the game," he said afterward, "but I saw an awful lot of positives out there."

The Cavaliers’ two most experienced players shared his assessment that team unity was no problem.

"I think we’re together," said Mike Miller, a 15-year veteran. "That’s not the question."

He added: "We knew it was going to be a process. Everybody wants it to happen now. So do we. We’ve got to keep grinding at it."

Shawn Marion’s 16 seasons have taught him that the media and the fans overreact to trends in small subsets of games.

"It’s going to take time," he said.

In the other locker room, Elton Brand, in his 16th season, also took the long view regarding Cleveland’s upside.

"It’s not even the halfway point of the season," said Brand, the most seasoned Hawk. "I expect them to be right near the top when it’s all said and done."

Being near the bottom in defensive rating — 23rd among 30 teams entering Tuesday — is the Cavaliers’ overriding on-court concern, especially with Anderson Varejao shelved for the season with a torn Achilles’ tendon.

Injuries and other maladies threaten to prey on the Cavaliers all season. As James swapped places in the starting five Tuesday with point guard Kyrie Irving, who skipped the two previous games with a bruised knee, Love’s evening was abbreviated by back spasms, and Marion sat out with a sprained ankle.

Yet, facing the team that has upstaged them as perhaps the most impressive in the conference, the Cavs nearly wiped out a third-quarter deficit of 17 points, charging to within 3 halfway through the final period. Irving assumed James’ scoring mantle with 35 points, saying, "I had no choice."

Love said, "We’ve got to fight this battle of attrition."

Continued underachieving would create major worries for the Cavaliers. James is contractually committed only through this season, and the enticement to move again, taking his talents to a more title-ready team, might be irresistible, especially if the end of an incomparable career is coming into view.

© 2014 The New York Times Company