Watanabe's most impressive number most of the night, however, was zero.
The senior guard achieved something that no teams of late have been able to do: stifle Otis Livingston II.
Averaging 26 points in the past four games, the Patriots junior guard could not escape Watanabe's shadow or wingspan. Livingston labored to just get shots and didn't score until less than two minutes remained at Smith Center. He finished with three points on 1-of-7 shooting and committed five turnovers.
"What he did today is hard," Colonials Coach Maurice Joseph said. "It is hard. And he did that against one of the quickest guards not in our league [but] in the country. That was pretty impressive. I was impressed on the sideline."
Watanabe is listed at 6 feet 9, but, as Patriots Coach Dave Paulsen said, "can move his feet like he's 5-9."
With help from his teammates, the Japanese-born senior prevented the 5-11 Livingston from using screens, collecting handoffs and breaking loose in transition.
"I was mentally prepared because I know I have to guard him for 40 minutes," Watanabe said. "It's not easy, but that's my job."
GW forward Bo Zeigler added, "It's a job no one wants to do for 40 minutes, guarding a quick, speedy guard who likes to come off ball screens and get a full head of steam."
With Livingston neutralized, the Colonials (9-10, 2-4 Atlantic 10) never trailed and improved to 19-2 in the all-time series, including 14-0 in Foggy Bottom and 9-0 since the Patriots joined the conference in 2013.
Watanabe received plenty of help: Zeigler scored 18 points on 9-of-11 shooting, most on dunks; freshman Terry Nolan Jr. posted 18 points, six assists, six steals and four rebounds; and Jair Bolden added 16 points.
Freshman Goanar Mar scored 17 points, Justin Kier had 13 and Jaire Grayer recorded 11 points, 10 rebounds and five assists for the Patriots (9-10, 3-3), who had been enjoying their finest start to conference play. They shot 51 percent but committed 18 turnovers — "a lot of unforced, panic-induced turnovers," Paulsen said.
The Colonials shot 64 percent in the first half to build a 15-point lead and 55 percent overall before a crowd of 2,215.
The Colonials rushed to a 22-7 lead as Zeigler contributed at both ends. George Mason couldn't match his athletic ability, and when Kier ventured into the lane, Zeigler's block triggered Nolan's fast-break layup.
Later, Zeigler's tap-in increased the lead to 15 before the midway mark of the first half.
"We came out with a ton of energy," Watanabe said. "Everyone was really active."
The Patriots responded with a 21-7 run, led by Ian Boyd's seven consecutive points and freshman Jevon Greene's seven-point surge. But with the lead down to 29-28, the Colonials went on a 15-1 spurt to end the half.
They made all five field goal attempts, including a three-pointer by Bolden and three-point shot and three-point play by Watanabe. The Patriots committed four turnovers on five possessions and did not make a field goal in the last four-plus minutes.
In the middle of it all, Zeigler's hustle for a loose ball on defense prompted Joseph to lean over and punch the air three times while yelling in delight.
"Guys were diving on the floor," Joseph said. "I was diving on the floor."
Zeigler began the second half with a dunk, the first of his four slams after intermission. The Patriots threw minor scares into the Colonials but never got closer than seven points. GW made 8 of 9 free throws down the stretch.
The key, though, was the defensive work on Livingston.
"If you can get him going downhill, I don't think there are many people who can stop him," Joseph said. "He's way too shifty, way too quick, so our goal was to keep him at neutral as long as we could. When he gets to second and third gear, he's a monster. We limited second and third gear."
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