USA TODAY Sports’ Jeff Zillgitt breaks down what the Celtics must do to survive their series with the cavaliers.

Boston Celtics point guard Isaiah Thomas has become a household name over the past two seasons, evolving from Sixth Man of the Year candidate to back-to-back All-Star to All-NBA Second Team member.

And of course, as we’re sure you’re aware by now, he’s only 5-foot-9.

But just how good could he be if he were, say, 6-foot-4?

“I’d be the best player ever, and everybody would think that,” Thomas said with a chuckle while making an appearance on Good Morning America on Friday. “No question about it.”

Hypothetical as it may be, humor him for a second. Playing a position headlined by Russell Westbrook, James Harden and Stephen Curry — who all stand at least a ½-foot taller — Thomas averaged 28.9 points (third-best in the NBA), led his Celtics to the No. 1 seed in the Eastern Conference and broke franchise records set by Larry Bird and John Havlicek.

“Best ever” is a tall order, of course, and part of the reason Thomas is such a gifted scorer is because he uses his height to his advantage. But based on his track record of proving his doubters wrong — and considering the fact that if he were taller and longer, the shortcomings of his game, particularly on the defensive end, would be much less significant — who are we to disagree?

“It’s always, ‘He’s good, and he’s 5-9.’ I’m trying to look past it, but I guess it’s never going to go away,” Thomas continued. “It’s always going to be, ‘Well, he’s 5-9.’ And I’m never gonna be OK with it.”

Thomas, whose…