PHOENIX -- The Dallas Mavericks have a major problem with Monta Ellis.

Actually, the Mavs have multiple Monta problems, both short term and long term. To put it bluntly, he’s a pain in the butt who isn’t producing.

The Mavs have no hope of making it out of the first round, regardless of their draw in the deep Western Conference, if Ellis doesn’t heat up. Then, assuming that Ellis opts out of the final year of his contract as expected, the Dallas front office has to figure out how much they’re willing to pay to keep an undersized shooting guard who will be 30 next season and has a history of rubbing his teammates the wrong way.

Monta Ellis will have to prove he can do more than just score if he wants a Chandler Parsons-esque deal this offseason. Jerome Miron/USA TODAY Sports

Let’s start with the immediate issue. Ellis is awful right now, hitting rock bottom in Sunday’s 92-86 loss to the Phoenix Suns, when he finished with 11 points on 4-of-22 shooting.

Talk about too much Monta.

Yet coach Rick Carlisle called play after play for him during crunch time. Ellis responded by missing all eight of his shots from the floor in the fourth quarter. He had seven bricks and a turnover in the final 5:04, as the Mavs blew a six-point lead.

So why keep calling Ellis’ number when he’s clearly ice cold? Carlisle’s answer is evidence of just how much the Mavs rely on their mercurial leading scorer.

“We’ve got to get shots. We’ve got to get shots,” Carlisle said, repeating himself for emphasis. “He’s the one guy who can get clean shots. And he’s getting good looks. I always believe he’s going to make the next one.

“My responsibility as a coach is to make sure we get shots. We can’t go places where clear shots are not going to be generated, and he’s been too good in these situations all year long. Hey, he had a bad shooting night. That’s the way it goes.”

A strong argument can be made that the Mavs would have been better off with small forward Chandler Parsons, last summer’s free agency prize who led the Mavs with 19 points in the loss, as the primary offensive initiator down the stretch. After all, Parsons’ pick-and-roll work with center Tyson Chandler played a huge role in the Mavs getting back in the game after a miserable first half, as he had seven points and an assist during Dallas’ 14-0 run in the third quarter.

But Parsons got only a couple of plays called for him after his pull-up jumper off a Chandler & Chandler pick-and-roll gave the Mavs their biggest lead of the night, putting them up six with 7:14 remaining. Dallas scored a grand total of two points in the next six-plus minutes, when Ellis missed five midrange jumpers and committed a turnover.

“Just because he’s off one night, he’s been a great closer for us all year long,” said Parsons, whose final pick-and-roll resulted in an offensive foul on Chandler with 2:17 remaining and the score tied. “We believe in him. We’re going to keep riding him, but when it comes to play-calling, it’s pretty much on coach.”

Added power forward Dirk Nowitzki, who hit a midrange jumper for the Mavs’ only points during that six-plus-minute stretch: “Monta had some shots that we’ll live with. He’s made those pull-up 15-, 16-footers off the screen-and-roll. That’s his shot. He’s made more than he’s missed for us this year.”

Ellis had nothing to say, refusing to stop to talk to reporters as he exited the locker room with headphones covering his ears. Ellis often bucks NBA rules by blowing off the media, particularly after poor performances.

We haven’t heard much from Ellis lately.

The Mavs continue to express confidence in Ellis as their closer -- and he does still lead the NBA in clutch points this season with 118, per NBA.com’s definition of the final five minutes of regulation or overtime with the score within five points -- but he’s been bad for almost two months now. Ellis is shooting 38.5 percent from the floor since Feb. 1.

Not coincidentally, the Mavs have been mediocre during that span with a 12-10 record.

Carlisle dismissed a follow-up question about Ellis’ extended slump by focusing on what he perceives to be the Mavs’ biggest problem.

“This is not a Monta Ellis shooting problem,” Carlisle said. “This is a Dallas Mavericks hard-play problem, all right? We don’t play hard all the time. And that’s a problem.

“It’s pretty clear that’s where our inconsistency is and we’ve got to get better. We’ve got to be a more together team. I believe that we can do it. We did it in the second half, but it’s work. It takes effort. It takes effort in the locker room, it takes sacrifice and we’ve got to be willing to do those things.”

Regardless of whether anyone will admit it on the record, Ellis is a big part of that problem. Folks in the Mavs organization have been fretting for weeks about the impact Ellis’ moodiness has on the team’s soul.

That, of course, isn’t a first for Ellis. He had trouble getting along with teammates during his tenure with the Golden State Warriors, who never won anything of note with Ellis as the go-to guy and made an addition-by-subtraction deal by shipping him off. The same was true with the Milwaukee Bucks.

(Quick aside: Too bad the Mavs don’t have a Stephen Curry type ready to take over as the go-to guy or a Klay Thompson clone to plug in Ellis’ spot in the lineup. That’s another issue: If the Mavs let Ellis go, they have to find another go-to guy.)

Those issues, along with Ellis’ offensive inefficiency, partially explain why he didn’t find much of a market for his services in the summer of 2013, when he opted out of the final year of his contract with the Bucks and turned down an offer to stay in Milwaukee.

Remember, the Mavs weren’t willing to offer Ellis much more than the midlevel exception until the team got desperate, tearing up the contract they agreed on with Devin Harris after discovering he needed complicated toe surgery. If Harris was healthy, the Mavs wouldn’t have had the cap space to give Ellis the three-year, $25 million deal that was still far below his asking price.

That contract was a bargain for the Mavs for Ellis’ first season and a half in Dallas. As recently as the All-Star break, it’d have been an easy decision for Dallas to re-sign Ellis with a handsome raise. Owner Mark Cuban would have gladly coughed up as much as the Mavs are allowed to give Ellis while owning only his early Bird rights.

That would mean Ellis would be paid $47 million over the first three years of his new deal -- which, of course, is $1 million more than what Chandler Parsons is making. And you better believe that matters to Ellis.

But Ellis’ value is dipping by the day. If you’re going to be high maintenance like Ellis is, you’d better be worth the headaches. Ellis sure as heck hasn’t been for the last couple of months.