During a timeout in the second half of a close game this season, Celtics coach Doc Rivers gathered his second unit at midcourt. The resting C’s joined the huddle off the bench; everyone but Paul Pierce and Rajon Rondo, that is.

Maybe it’s reading too much into that situation. Maybe Pierce and Rondo were resting their legs for the fourth quarter. Or maybe they were tuning out Rivers.

It’s practically inevitable in a sport where the average player owns a guaranteed contract worth twice that of his coach. There’s a reason Patriots players still fear Bill Belichick after 13 seasons, and there’s a reason Red Sox players stuffed themselves with fried chicken at the end of Terry Francona’s eight-year run.

While NFL contracts remain non-guaranteed, Rivers finds himself in the same boat as Francona: A revered coach with championship credentials struggling throughout a long season to keep a veteran team focused on another title run.

Since arriving in Boston nine years ago, Rivers filled his bag of coaching tricks, earning a reputation that helped lure free agents like Courtney Lee, Jeff Green and Jason Terry to a cold-weather city this summer. Now, he’s emptying it.

After his team hovered around .500 through the first month, Rivers publicly called these Celtics “a soft team.” They responded in their next six games -- winning four and losing two by a pair of baskets -- and then became complacent again.

During a 2-8 stretch through New Year’s, Rivers told WEEI, “We’re not consistent enough. Every night, there are one or two guys who don’t do their jobs.”

Meanwhile, everyone from Fab Melo to Pierce landed on the trading block. Only two guys whose consistent effort deservedly goes unquestioned appeared to be safe, since Kevin Garnett holds a no-trade clause (for good reason) and Ainge rightfully wouldn’t include Bradley in a deal for DeMarcus Cousins.

As a result, the Celtics won six straight by an average of 11 points and team president Danny Ainge called off the trade dogs, claiming it “doesn’t make a lot of sense to radically change the team when you’re trying to win it all.”

So, complacency crept in again during their current skid to three teams with a combined sub-.500 record. That’s when Rivers pulled out the only rabbit left in his hat after the C’s embarrassing 103-88 loss to the Pistons on Sunday night.

“They want the easy way out,” Rivers told reporters. “They want to win easy, and I told them the only way you’re going to win easy is you’re going to have to play hard. The harder you play, the easier the games become.

“We’re taking the wrong approach. I’ve got to either find the right combination, the right guys, or we’re going to get some guys out of here. It’s the bottom line.”

Rivers added: “We are playing awful. I’m clearly not doing my job with this team. And I’m serious. I’m not trying to take a bullet for the team, and I told them that. I said, ‘We’ve got to find something where, every night, all 12 guys play the same way.’ ... I’ve got to figure it out, because I don’t think the guys are honest with each other. I just don’t think we’ve committed to being a good basketball team.”

Indeed, Rivers has tried 11 different starting lineups. In the meantime, among other issues, he’s watched Rondo repeatedly revert to immature behavior, called out Jeff Green on multiple occasions, listened as Terry admitted his distaste for practice and shielded Courtney Lee during his inconsistent season.

Maybe Rondo and Pierce have grown tired of hearing their names in trade discussions. Maybe comfort breeds complacency, since Pierce and the three Celtics on veteran minimum contracts (Jason Collins, Leandro Barbosa, Chris Wilcox) are the only players who don’t have money owed to them through the 2014-15 season. And maybe the C’s are tuning out Doc Rivers.

Only, while 23-of-30 NBA teams have replaced coaches since 2010, Rivers has more tenure than every peer but Spurs coach Gregg Popovich, and Doc signed a five-year, $35 million extension prior to last season.

While Ainge tempered his coach’s trade threats, the C’s president also pledged his allegiance to his longtime friend. So, Rivers will continue to huddle the Celtics together during timeouts; whether Pierce, Rondo and others join him remains to be seen.