Like it or not, the Boston Celtics need one more All-Star-caliber player in order to have a chance to contend with the NBA’s elite teams year after year.

The Celtics have performed admirably this season without Gordon Hayward, as Brad Stevens — the best asset in the NBA — has piloted Boston to a top-two seed in the Eastern Conference despite having to manage a wealth of youth and inexperience.

But when Hayward comes back at full-strength, likely in October, the Celtics still will be a notch below the Golden State Warriors and Houston Rockets.

Enter: Kawhi Leonard.

The San Antonio Spurs star forward has missed all but nine games this season with a mysterious quad injury, and reports of his friction with head coach Gregg Popovich and the Spurs organization have many thinking that Leonard’s days in San Antonio are numbered.

So, naturally, the Leonard-to-Boston rumors already have begun thanks to Jalen Rose floating the idea on ESPN”s “NBA Countdown.”

If Leonard is indeed made available in trade talks this summer, the Celtics would be foolish not to try and pry the 2014 NBA Finals MVP away from the Spurs.

Boston’s championship window might just be opening, but there’s no telling how long it will remain so. With Kyrie Irving (26), Al Horford (31) and Hayward (28) all in their prime, the Celtics and Danny Ainge would be wise to strike while the iron’s hot and add another superstar to the mix, especially one with Leonard’s unique skills.

The 26-year-old is the best one-on-one defender in the league when healthy, something he has shown time and time again. Leonard’s length, intensity, positioning, athleticism and alien-like arms are so effective on the defensive end that it caused NBA teams to isolate him defensively during the 2016-17 season, in order to take him out of the equation on defense. Teams would take Leonard’s man and stick him in the corner, forcing the other members of the Spurs to defend one-on-one without the possibility of help coming from Leonard.

The fact is there is no better individual defender in the NBA than Leonard, and that is a valuable weapon to have against the likes of Kevin Durant, James Harden, Stephen Curry and LeBron James.

But Leonard is about a whole lot more than defense. The San Diego State product became a dangerous offensive player during the final years of the Tim Duncan era and transformed into an MVP candidate following the Spurs’ 2014 NBA championship. Over the past three seasons, Leonard has gone from the third/fourth option on offense to a guy who was three percentage points away from being a 50-40-90 guy during the 2015-16 season.

Leonard’s complete dominance was on full display during Game 1 of the 2017 Western Conference finals against the Golden State Warriors, when he led the Spurs to a 25-point lead before leaving after suffering an ankle injury. Leonard scored 26 points in 24 minutes while giving the eventual NBA champions fits on both ends of the floor.

The Celtics don’t currently have a player who has the ability to do that.

Of course, the price for Leonard would be high, but one the Celtics should be willing to pay. Boston has multiple first-round picks it could offer along with young stars Jaylen Brown, Jayson Tatum and Terry Rozier. Some combination of those assets would allow the Spurs to rebuild on the fly while giving Boston its missing piece.

While parting with potential stars like Brown and Tatum certainly isn’t appealing, getting a top five NBA player in return is well worth the price. Brown and Tatum have loads of potential, but it’s unlikely that either of them will be as good as Leonard in their prime. And even if one of them eclipses Leonard’s peak, the Celtics’ other stars will be on their last leg when the ascension is realized.

If Leonard becomes available this summer, the Celtics should jump at the opportunity to acquire the superstar, and what could be banners 18, 19 and even 20 along with him.

Thumbnail photo via Jerome Miron/USA TODAY Sports Images