Isaiah Thomas entered Monday night leading all NBA players in fourth-quarter scoring, averaging a whopping 10 points per final frame. Much to the chagrin of the Detroit Pistons, the Boston Celtics All-Star guard decided that number wasn’t high enough:

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“The King in the Fourth” ruled once again on Monday, scoring 24 of his game-high 41 points in the fourth quarter to stave off the Pistons’ attempt at a comeback and seal a 113-109 win. Another late-stage explosion by Thomas helped extend Boston’s winning streak to four games and improve the Celtics’ record to 30-18. The victory, combined with another disappointing loss for the slumping Cleveland Cavaliers, drew the C’s to within 2 1/2 games of LeBron James and company for the top spot in the Eastern Conference.

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They wouldn’t be within striking distance of the defending champs without the remarkable scoring skill of the 5-foot-9 Thomas, who last week was named as a reserve to the Eastern Conference All-Star team for the second straight season, and whom many believed should have been voted in by fans, media members and his fellow players as a starter on the strength of the best half-season of his career. The 27-year-old triggerman has now scored:

• 20 or more points in the fourth quarter alone on four separate occasions this season — nobody else has done it more than once (and Thomas himself hadn’t done it at all before Dec. 20);

• 15 or more points in the fourth nine times, four more than second-place Russell Westbrook;

• 20 or more points in a game in 32 straight outings, the second-longest streak in Celtics history; and

• 40 or more four times, behind only Westbrook, James Harden, Jimmy Butler and Anthony Davis for the 2016-17 league lead, after never hitting the 40-point mark before Dec. 20.

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The Celtics needed every Thomas point to hold off the Pistons, who erased an 11-point deficit with a 14-3 early-fourth spurt behind buckets from Marcus Morris and reserve point guard Ish Smith to knot the score at 88 with seven minutes left. From that point on, though, Thomas absolutely took over, mixing in downhill attacks to get to the line, stop-on-a-dime pull-ups and stepbacks, and hide-and-seek pick-and-roll play behind screens to fire 3s. Add it all up, and Thomas went 6-for-7 from the field and 7-for-7 from the stripe for 22 points in the final seven minutes alone.

You’d call Thomas’ performance unbelievable … if it wasn’t precisely the kind of thing we’d come to expect from the Celtics’ diminutive destroyer. After the game. Pistons coach Stan Van Gundy couldn’t believe he’d let Thomas make mincemeat out of his defense, too. From Adam Himmelsbach of the Boston Globe:

“The only person I’m upset at right now is myself,” Van Gundy said. “The fourth quarter — I’ve coached like 800 games in this league; you’ve got to do a better job than what I did.” […]

“Shoot, triple-team him, run everybody at him,” he said. “Bottom line is, when they hit the fourth quarter — and I don’t mean any disrespect to any of their other players — he’s playing so well right now that he’s just a one-man team. Make somebody else do something, and I didn’t do that, and that’s on me.”

To hear Celtics coach Brad Stevens tell it, though, Van Gundy did catch Boston off-guard a bit with Detroit’s mix-and-match coverages. It’s just that, in Thomas, the C’s have the answer for damn near any question a defense can think to ask these days. From Doug Alden of The Associated Press:

“[Thomas] was unbelievable — again,” coach Brad Stevens said. “They kind of kept us off balance with their coverages so we just tried to get him off the ball some. And then when he got going late, he just got going so it didn’t matter he was off the ball or on the ball.” […]

“I always just try to get a little more aggressive to score, to make plays,” Thomas said. “They started switching a lot in the fourth quarter and then Brad calls in some really good plays to get the spacing right. We had nice spacing, things opened up for me and I just took advantage of it.”

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