David Fizdale is as much a salesman as he is a coach. The two go hand in hand.

So after lottery picks Kevin Knox and Frank Ntilikina were criticized by scouts and NBA executives in a Marc Berman story in The Post this week, Fizdale strongly defended his young players.

That’s his job. But Knox and Ntilikina need to play better, too, and this criticism can work to the players’ advantage.

It did Saturday night for Knox, who scored a season-high 26 points as the Knicks stormed back from 14 down in the fourth quarter to come away with a thrilling, 136-134, overtime win over the Bucks at the Garden.

Knox was anything but soft.

As for Ntilikina, he did not play — coach’s decision.

“This was a big game for me, I grew up today,” said Knox — who shot 9-for-20, including 5-for-12 from 3-point range, with four rebounds, four assists, one steal and one block over 37 minutes off the bench. “Just being able to be out there in the fourth quarter, overtime, a big-time game against a big-time playoff team, it was good for me to be out there and learn from that.”

Thirteen of Knox’s points came in the fourth quarter. The forward did not score in overtime, but the confidence Fizdale showed in him worked wonders.

“Fiz is always going to have confidence in me,” Knox said. “He just wants me to keep playing hard. He talked to me about that the other day. It shows how much confidence in me to keep me out there the whole game … I’m ready for the next game.”

His teammates were thrilled. As Tim Hardaway Jr. left the locker room, he yelled, “Hell yeah, Kevin Knox.”

Noted Hardaway: “We weren’t backing off of this kid, and he came in to work, he came to practice, every single day, got there early, stays late, puts up extra shots, asks questions. Coach got on him a little bit, but he took it to heart and turned it from a negative thing into a positive thing. That’s what this is all about.”

That is how you grow up in the NBA.

“This is the culture we’re trying to build,” Hardaway said. “It’s the definition of it. He came out here ready to play against one of the top two teams in the East and he showed a lot of heart. He’s definitely one of the reasons why we won this game.”

Fizdale said he was most proud of the way Knox, 19, competed despite criticism, especially against a Bucks team that features superstar Giannis Antetokounmpo, who battled for 33 points and 19 rebounds but was hounded into six turnovers by the Knicks.

“I only hear this stuff from you guys, but obviously it sounds like he has been receiving some criticism in the press and that’s cool,” Fizdale said. “But the way he responded tonight, knowing that the way the world is on him and this is that kind of city, but he asked for this. He wanted to be a Knick, and he understood what comes with it, and the kid comes in every day and does his work. He’ll have some more lows in this deal, where it goes up and down for him, but I just like his approach and his approach will get him there.”

Fizdale can make it all work for him as a meaningful coaching tool.

That’s what coaching is all about, and that was not lost on Fizdale. As he left the Garden, The Post asked him the importance of getting that coaching message across to his players.

Fizdale smiled and said, “Without me being the bad guy.”

Fizdale and Knox made the most of that message Saturday night.

Knox came into the night averaging 7.5 points. The 17th game of his NBA career showed impressive results and some moxie.

Expectations can be difficult in the NBA, a league where the rookies get younger every season. There is nothing wrong with demanding improvement from your young players, who are lottery picks.

It’s OK to push them hard, and Kevin Knox responded with much promise for the future.