The Knicks’ decision to waive small forward Troy Williams on Monday has provided undrafted Arizona guard Allonzo Trier a puncher’s chance at making the 15-man roster following his solid — if overlooked — summer-league performance.

Trier is on a two-way G-League contract, allowing him to be on the Knicks’ roster for a maximum of 45 days, with the clock stopping in early April.

If Trier looks good in training camp, the two-way deal can be ripped up and he can vault into a 15-man roster spot. Williams’ surprising waiver means the Knicks now have the allotted 15 players for their NBA roster, along with a pair of two-way guys: Trier and Isaiah Hicks.

Williams’ contract would have been only partially guaranteed on Aug. 1 and coach David Fizdale felt he would not get much time this season. His dazzling athleticism was much-needed late last season, but he’s known to be turnover-prone and he didn’t seem to grow in that area. Fizdale is trying to strike a balance between athleticism and cerebral play.

During the summer league in Las Vegas, president Steve Mills and general manager Scott Perry gave no indication they want center Joakim Noah to battle for a roster spot. Sept. 1 marks the first date the Knicks can waive Noah in the stretch provision and open up significant 2019 salary-cap savings.

If Noah goes, Trier can vie for the 15-man roster without the embarrassment of Mills releasing Ron Baker, who is still rehabbing from shoulder surgery one year after signing an eyebrow-raising two-year, $9 million deal.

The summer league ended Tuesday night with the Knicks’ first-round pick Kevin Knox getting first team honors and second-rounder Mitchell Robinson earning plaudits for his shot-blocking and lack of rust after having not played in a game in more than a year.

Trier? The 6-foot-5 guard, undrafted but undaunted, was overshadowed. Forced to play the final two games at point guard because of Frank Ntilikina’s groin injury, Trier held up well and finished averaging 17 points on 45 percent shooting.

“I competed well and played well,’’ Trier said in Las Vegas. “I didn’t feel I’m a step slow or behind any of these guys. That’s how I am and believe in myself.”

The Knicks are still considering signing a 16th player — a veteran rebounding big man with the requirement he be a character guy who won’t fret about playing time. (By recent history, Noah seeks playing time).

“I know what I’ve done throughout my career and what kind of player I am,’’ Trier said. “I’m not trying to compete with Kevin and Mitchell. These guys are great players. I’m getting to know them, gaining chemistry. I’m a competitor. I know I can compete with everybody here. I’m not worried about trying to sell anybody. My game speaks for itself.

“I think I’ve played with good pace and under control. I think I had great performances out there. I’ve done myself well.’’

Trier spoke with the confidence of a player who was considered a lottery pick entering his sophomore year at Arizona. He subsequently failed two tests for a steroids-related substance, one during his sophomore season and one in his junior year. Sources indicate, however, he fell out of the draft because teams were also concerned about his shot-happy nature and questioned his desire to distribute the ball.

Trier didn’t look completely at ease running the point, but the Knicks have made it a top priority that he work on that part. They know he’s a shot-maker and the Ntilikina injury was a blessing in disguise since it forced him to run the point. The Knicks sat Trier during the final game, having seen enough.

“It’s not something I’m uncomfortable with doing,’’ said Trier, who played some point at Arizona. “It’s how they want me to play [at summer league]. I get us in offense. I’m learning how the coaching staff wants us to play point guard here and also learning from Frank.

“It’s a little bit different not playing off the ball and trying to always be in attack mode. I’m trying to get us in the offense and get the ball to the right guy.”