VanVleet said Ibaka, who started for the first time this season, has more talent than the typical NBA reserve.
''Serge is a starter,'' VanVleet said. ''He took that sacrifice to come off the bench for the betterment of our team, but he's still a starting-caliber big in this league, and a very good one at that.''
Ibaka has recorded double-doubles in three of his past four games.
''He's feeling good about himself,'' Lowry said. ''We just need him to play at that level.''
Wizards coach Scott Brooks had Ibaka on his roster for six seasons in Oklahoma City, and still has a fondness for the Congolese big man's intense style.
''He's as passionate and competitive and angry on the court as I've seen any player, and I love that about him,'' Brooks said of Ibaka. ''He's hard to guard, he's strong.''
''Any win is tough in this league, especially when you're missing half your team,'' Raptors coach Nick Nurse said.
Siakam and Gasol were the only two players to start each of Toronto's first 27 games. Powell had started 16 of the past 19, including 11 in place of Lowry while the five-time All-Star was recovering from an injured left thumb.
VanVleet had missed Toronto's past five games because of a right knee contusion.
''I'd like to think that I increased our chances of winning tonight, regardless of how ugly it was,'' VanVleet said.
''I feel like we should have won,'' Beal said. ''We had enough flow and juice to win. Down the stretch, we kind of got away from ourselves. We weren't defending. They made some tough shots down the stretch, too.''
Smith made all nine of his field-goal attempts, including four from 3-point range. He also shot 4 for 4 at the free throw line.
''I expect him not to miss tomorrow night, either,'' Brooks joked. The Wizards visit Philadelphia on Saturday.
Beal shot 3 for 10 from 3-point range while teammate Davis Bertans went 2 for 12 from long range. Bertans finished with 10 points.
Toronto led 96-85 to begin the final quarter, but Beal and Admiral Schofield made back-to-back 3-pointers to cut the deficit to two points, and Smith's 3-pointer with 5:21 to go tied it at 107-107.
McCaw hit a tiebreaking 3 with 3:02 remaining and, after Beal missed a 3 that would have tied the score, Lowry answered with a 3 with 2:00 left, putting the Raptors up 116-110.
Beal and Troy Brown Jr. each made baskets in the final 21 seconds to cut the deficit to two points, but VanVleet made four free throws down the stretch to preserve the win.
The Raptors led 40-23 after one, their highest-scoring first quarter of the season, and were up 68-52 at halftime.
Wizards: Rookie F Rui Hachimura (groin) sat for the second straight game. Hachimura is expected to miss at least five games. . C Moritz Wagner (sprained left ankle) missed his fourth straight game. . Washington is 4-12 on the road.
Raptors: Lowry led Toronto with nine assists. . Anunoby has missed just one start for Toronto this season, sitting out a Nov. 13 game at Portland after being poked in the eye in the previous game, a road loss to the Clippers. . McCaw made his first start of the season and scored a season-high 11 points. . Toronto's 34 free throws made and 44 attempts were both season-highs.
LIFE BEGINS AT 40
Toronto has scored 40 or more points in a quarter six times this season, doing so at least once in all four quarters. The Raptors have scored at least 40 in the second three times, doing so most recently in Wednesday's win at Detroit. Toronto set a season high for points in a quarter with a 45-point second in a Nov. 8 win at New Orleans.
Lowry and injured G Matt Thomas made cameo appearances as cannon dolls Thursday in a National Ballet of Canada performance of ''The Nutcracker.'' Toronto Maple Leafs players Mitch Marner and Auston Matthews played the same roles in a performance last year.
Wizards: Visit Philadelphia on Saturday.
Raptors: Host Dallas on Sunday.
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