WASHINGTON -- Whether with the gold medal-winning USA Basketball team or on his own, DeMar DeRozan put in work this offseason. His NBA opponents are learning just how much.

DeRozan continued his season-opening scoring surge with 40 points and the Toronto Raptors continued their regular-season dominance over the Washington Wizards with a 113-103 win on Wednesday night.

The Olympian had 28 points in the second half and eight of the final 11 for the Raptors (3-1). DeRozan also scored 40 in the season opener and has at least 30 points in all four games.

"I'm just a student of the game. I work extremely hard in the summertime, extremely hard," the wing guard said. "I just try and put everything together, be a student of the game while working, always feeling like I'm new to the game so I can soak up as much as possible. I try to release it once I get out there on the court."

Signed to a five-year, $139 million contract this summer, DeRozan is averaging 36.5 points.

"He's playing on another level right now, man," said backcourt partner Kyle Lowry, who added 18 points. "He's making my life a lot easier and making, I think, everybody on our team's life a lot easier. He's saving possessions, he's creating possessions, he's creating offense."

John Wall had 33 points and 11 assists for the Wizards (0-3), but mistakes -- and DeRozan -- ruined their home opener. Toronto converted 21 turnovers by Washington into 30 points.

Otto Porter had 23 points and 13 rebounds for the Wizards.

"Execution. Taking care of the ball. Movement. This right now is defense," said Porter as he ticked off reasons for the slow start. "Everybody needs to be on the same page. Getting stops. Just playing hard."

DeRozan made 14 of 23 shots from the field, 11 of 16 free throws and closed the game with a rare 3-pointer in Toronto's first road game.

"Tonight he hit a 3," Lowry joked. "Now y'all can't say he's not a 3-point shooter -- 1 for 2, 1 for 2, man, he was 50 percent. Y'all can't get mad at him now. Now what? He scored 40 points and hit a 3. Whatcha'll gonna say now?"

All that scoring came despite an ankle tweak.

"It sucks, but I try to fight through it and deal with it," DeRozan said.

The Wizards must deal with another late-game collapse and their first 0-3 start since the 2013-14 season. That edition finished 44-38.

Trailing 56-54 at halftime, Toronto outscored Washington 30-19 in the quarter with DeRozan scoring 15 points on 7-of-9 shooting from the field.

Wall's fast-break approach flipped the momentum as his steal and reverse layup tied the score 92-92 midway through the fourth quarter. That surge was met with an 8-2 spurt that put the Raptors ahead for good.

"There's a few things that we have to correct," Wizards coach Scott Brooks said. "Tonight the points off turnovers. ... That's hard to overcome."

Terrance Ross had 15 points for the Raptors.

Toronto has won eight straight regular-season games over Washington, but the Wizards swept the Raptors 4-0 in the first round of the 2015 playoffs.

Bradley Beal and Marcin Gortat each scored 15 for the Wizards, who shot 58.3 percent from the field. Toronto hit 55.8 percent of its attempts.

Wall scored 16 points during a first half in which Washington led 27-15, then trailed by eight in the second quarter thanks to its second unit's struggles before rallying for a 56-54 halftime lead. The Wizards shot 64.7 percent from the field but committed 12 turnovers before the crowd of 19,581.

Lowry left the game briefly in the first half with a cut over his eye that required three stitches.

NOTES: The Wizards were one of four teams to open the season with two road games. Eight of their next 11 games are at home. The Wizards host the Hawks on Friday. Washington lost its season opener 114-99 at Atlanta on Oct. 27. ... Raptors G DeMar DeRozan played in his 525th game, tying Jose Calderon for second most in franchise history and moving 17 games behind Morris Peterson (542). ... Washington's last regular-season win over Toronto entering Wednesday came Feb. 27, 2014. The Raptors went 10-1 in the previous three seasons. ... Toronto returns home to face Miami on Friday. The Raptors play five of their first six games at Air Canada Centre.