Celtics can’t let the Kyrie Irving deal fall through now

At 25, Kyrie Irving’s best basketball is ahead of him. Gregory Shamus/Getty Images

Danny Ainge and the Celtics are victims of their own success and sales pitch. They’ve done such a good job of selling the Parishioners of the Parquet on the value of their picks and their players that when they bundled some of them together to acquire the elusive Transformative Player there was a reflexive revolt over parting with so many assets.

The Celtics trade for Kyrie Irving was still on hold on Monday after the Cleveland Cavaliers expressed reservations about the condition of Isaiah Thomas’s hip following a physical last Friday. Cleveland is expected to try to coax more compensation out of the Celtics. (Don’t the Cavs kind of owe Ainge in perpetuity for taking Ricky Davis?)

There are some Celtics fans who want to use Thomas’s injured hip as an excuse for the Celtics to pull out of the Irving trade. That’s how attached they are to IT; glue-guy Jae Crowder; Ante Zizic, who has never played a single minute in the NBA; and the last of the Brooklyn draft picks. The Celtics have preached the gospel to the masses and now they can’t convince the true believers that part of the homily was exaggerated for effect.

I was overseas when this deal was announced, and I was stunned to read the reaction back home. Instead of hailing Ainge for finally cashing in his assets for a 25-year-old superstar who is one of the most mesmerizing individual offensive talents in the league and has tormented the Celtics in the postseason, Danny the Dealer has been criticized for surrendering too much. That chorus of criticism will only increase if the Celtics have to tack on another piece. Don’t listen to them, Danny. Close this deal with Cleveland. Irving is worth it. He is a bigger, younger, healthier, purer shooting version of Thomas. He already has one of the biggest shots in NBA history on his résumé. His best basketball is ahead of him.

Thomas earned All-NBA honors and a place in the hearts of Boston sports fans with his irrepressible joy, clutch play, and grace in the face of tragedy. But it’s reasonable for Cavaliers doctors to look at Thomas’s hip and question how well or how quickly it will heal. I think if Thomas already had his max contract he would have elected to have surgery on the labrum in his hip, instead of going the rehab route.

It’s understandable why the Celtics would balk at adding to the deal, but if it takes a lottery protected 2019 first-round pick to placate the Cavaliers so be it. Barring a catastrophe, the Celtics sweetener pick would be 25 or later. Don’t let the next R.J. Hunter, Fab Melo, JaJuan Johnson or J.R. Giddens stand in the way of consummating this deal. The Green still have a collection of other more valuable picks in 2018 and 2019.

A late first-round pick for a contending team often is more desirable in theory than in practice. This is the problem for the Celtics. They do such a good job of hard-selling us on the inflated value of their players and picks in theory that when they trade them away Celtics supporters experience separation anxiety. They can’t escape the reality distortion field the team has constructed to see the player for who or what he really is — expendable.

This is the case with Crowder, a darling of advanced analytics who fits perfectly into the coveted 3-and-D category — a wing player who can defend multiple positions and knock down the 3-point shot. He has become as overvalued as the player he was acquired for — Rajon Rondo.

For all the Crowderophiles, he shot 35.2 percent from 3-point range in the playoffs, and his career playoff 3-point percentage is 32.2 percent. In the Eastern Conference Finals, the Cavaliers were plus-77 with Crowder on the court and a plus-23 with him off it. Cleveland shot 54.3 percent with Crowder on the court and 51.5 percent with him off the court.

Crowder is a hard-nosed and versatile defender, but Marcus Smart, who shot better than Crowder from three in the postseason (39.7 percent), can fill that role. The Celtics had 10 three-man combinations last season that logged at least 200 minutes together and had a defensive rating below 100 points allowed per 100 possessions. Smart was a part of eight of those trios, including the top four. Crowder was a part of four, half included Smart.

Crowder’s impact is bigger on paper (or a computer screen) than on the court in the playoffs. His team-friendly contract and eye-popping plus/minus numbers (plus-349 last season) dissemble his true value, which like his role was going to be diminished with Gordon Hayward and rookie Jayson Tatum around.

There is a history of overrating and overvaluing those who don the green. Boston.com conducted a poll in which the majority of respondents did not want to surrender Al Jefferson for Kevin Garnett. Kendrick Perkins practically became a martyr after he was dealt to Oklahoma City in 2011. Rondo was defended like a family member.

The paradox of the Irving trade is that Ainge has done exactly what many have been clamoring for him to do with the Brooklyn picks.

When the Celtics fleeced the Nets the expectation was that they would parlay some of the picks into established All-Star talent to expedite Banner 18. That’s why fans practically booed Celtics owner Wyc Grousbeck out of the building when he announced the selection of Jaylen Brown in 2016.

At the time of the Brooklyn hoops heist, virtually no one expected that Ainge would use all four picks in the draft. Yet, now that he has used the last one to acquire a former No. 1 pick in his prime he is being condemned for doing exactly what most Celtics fans clamored for initially. It’s nonsensical.

Just as the key to the KG trade was not relenting on Rondo, the key to the Irving deal is keeping Brown and Tatum. Ainge’s modus operandi is to bundle multiple assets in a deal to protect the ones he really doesn’t want to surrender. Plus, the contracts of Thomas and Crowder were necessary to make the money match up under the NBA’s byzantine trade rules.

Ainge remains an unsentimental realist. Elite talent wins in the NBA. The underestimated, overachieving version of the Celtics had reached its peak. To go further, the Celtics need more high-end talent, more shot-creators. The Celtics had one of those last year, Thomas. Crowder does not fit into that category. Zizic never will.

This deal is too important for Boston to fail now.