Doc Rivers cannot play the NBA's Sixth Man of the Year as his sixth man.

When trying to comprehend how the LA Clippers have squandered a 3-1 series advantage over the Denver Nuggets -- and in spectacular fashion, by losing a double-digit second-half lead for the second straight game in Denver's 111-98 Game 6 win -- this is as good a place to start as any.

The Clippers' head coach quietly used JaMychal Green as his first big man off the bench Sunday. And it was a prudent decision because Montrezl Harrell, whose emotional acceptance of the Sixth Man honor has faded, has been plainly ineffective in this series.

The Nuggets have impressively rallied from down 16 in Game 5 and down 19 in Game 6 to force Game 7 on Tuesday (9 p.m. ET on ESPN). Nikola Jokic, who had 34 points (his most this postseason), is an All-NBA player who is performing like one. He's hard to handle, and he has been playing with purpose.

In the past two games, the Clippers have been outscored by 30 points when Jokic and Harrell have been on the court together in the second half. If you want to know why the Clippers blew those big leads, that is at the heart of it.

Jokic is shooting 64% when Harrell is the primary defender against him in the series, according to ESPN Stats & Information research. When starter Ivica Zubac is on Jokic, it's down to 49%. When it's anyone else, which happens in a switching defense, it's 54%.

"I've got 1,000 coaches. We have five analytical guys. I don't think there's anything we don't see," Rivers said about the lineup data. "Sometimes watch the game and then add up that [plus/minus]. Just watch it before you make [a] critique."

It's fine for Rivers to defend Harrell, as he should. And look, Harrell didn't win Defensive Player of the Year. He's not expected to stop Jokic; no one can. However, Harrell has also been miserable with the ball.

He won the Sixth Man honor because he averaged almost 19 points per game this season. In this series, he has averaged just 10.3.

Add in three-time Sixth Man of the Year winner Lou Williams, the other main cog in the team's often devastating bench, who is averaging nearly eight points less per game in this series, and you can start to piece together why the Clippers are not looking like championship material at the moment.

Secondly, for everything Rivers has going for him as a coach, he has not been able to press the right buttons.

In the third quarter, even before the Clippers lost the lead, Rivers was talking with his assistant coaches about red lights popping on the dashboard. He saw spirit draining. He implored his team during a timeout to increase their pace on offense. He benched Landry Shamet in favor of Reggie Jackson.

And afterward, he had no answers.

"I don't know [what the message is] yet, I'll let you know," Rivers said. "I have no idea [about the blown leads], honestly. It will take me watching the game again."

Rivers briskly swatted away a reference to blowing a 3-1 lead to the Houston Rockets back in 2015 -- there was a blown 19-point lead in Game 6 in that series as well -- saying this is completely different.

That's true, it is different. But Rivers absolutely does not want a third 3-1 series loss on his record, especially with a team that is constructed to win a championship immediately. Per ESPN Stats & Information research, Rivers is the only coach in NBA history with multiple 3-1 blown series leads.

Third, there is something unusual happening with the Nuggets. They seem to be more comfortable playing under pressure than not. Meanwhile, the Clippers seem to tighten up when they have leads.

It's hard to pinpoint whether there is some embedded reason in the personality of the Nuggets or what they've gone through -- they reported to Orlando, Florida, two months ago with just eight healthy players because COVID-19 and injuries hit them hard -- but they respond to it.

They have won five consecutive elimination games. Even with allowing for the bubble neutralizing home-court advantage, this is still extremely impressive. And within that number, it's the way they keep cheating elimination.

The Utah Jazz are probably still trying to come to terms with losing a 15-point lead in the second half of Game 5 back in the first round. The Nuggets have already slapped two such comebacks on the Clippers with their backs to the wall.

Jokic, normally a statue when it comes to showing emotion, appears to be letting his feelings out more even as he's supposed to be getting squeezed.

"It may sound weird or whatever, but we don't care [about having to make the comebacks]," Jokic said. "Coach said before the game in the meeting, 'Don't forget to have fun.' In the third and fourth quarter we were having fun."

The Clippers, as Rivers described, were not. It shows in their performance. Just take a look at open shots. The Clippers just haven't been making them in the second half.

In Game 5, the Clippers were 12-of-17 on uncontested shots in the first half, then 6-of-15 in the second half. On Sunday, they made 9-of-14 open looks in the first half, going up 19. In the second half, they were 6-of-14, including 1-of-7 on 3-pointers.

Why has the team not been facing elimination shooting like this?

"We're still in the driver seat. It's not a panic mode. We have a Game 7," Clippers star Paul George said. "I like our odds with our group."

Fair enough. There are some outlier situations here that could correct themselves. Then again, this isn't exactly a small sample from Denver. The Nuggets' case for being the better team is getting compelling.

"We find it funny that the narrative is, 'Oh, the Nuggets are a cute team, what a good story,'" coach Mike Malone said. "We were second in the West last year. ... Most of this year we were the No. 2 seed in the West until after the All-Star break we lost hold of that.

"I think it comes down to a tremendous belief and confidence in who we are, what we're about and what we're trying to accomplish."