TORONTO -- Dwane Casey had just become the winningest coach in Toronto Raptors history but he was more interested in talking about the work left to do rather than reflect on the accomplishment.

"We're not there yet," Casey said after the Raptors defeated the Milwaukee Bucks 106-87 Sunday night for the 157th victory of his Toronto coaching career, passing Sam Mitchell for the most with the franchise.

"We started 30th in the league in defense, (we've done) a lot of building, and we're still building," said Casey, who is in his fifth season as Raptors head coach. "Nobody wants to hear that, but we're in the middle of a process of where we need to go and we're not done."

Center Jonas Valanciunas scored 19 points, and reserve forward Patrick Patterson added 16 as the Raptors pulled away in the fourth quarter before a sellout crowd of 19,800 at Air Canada Centre.

The Raptors are off to a 3-0 start for the third time in franchise history. The most recent occurrence was 2008-09.

"I think we just went out there tonight and played our game," said point guard Kyle Lowry, who 15 points, seven assists and five rebounds. "We are getting a lot more comfortable with each other, feeling out where we are going to be and the spots on the floor where we need to be at."

Toronto led by 14 at the half and by 10 after three quarters before the Bucks (0-3) cut the lead to six points early in the fourth. But reserve guard Terrence Ross and Patterson hit back-to-back 3-pointers keying a 14-0 run as the Raptors turned it into a laugher.

"From there, we just couldn't catch our breath, we couldn't make a shot or we turned the ball over," said Bucks head coach Jason Kidd. "It was 9:52 (to go), and from that point on they go 5-for-7 from the 3-point line and they push the lead back up."

"There was a lot of good things," Kidd said. "We played three quarters, again in the fourth we let go of the rope. So, we have to get better at that."

Forward Giannis Antetokounmpo led the Bucks with 20 points and nine rebounds. Center Greg Monroe added 14 points, six rebounds and five assists for Milwaukee (0-3).

Guard Greivis Vasquez, who was traded to Milwaukee on draft night after two seasons in Toronto, had nine points, four assists and three rebounds off the bench in what he called an "emotional" return.

"They shoot a lot of 3s, they've got great shooters out there," Vasquez said of the Raptors, who made five of their 11 3-pointers on the night in the fourth quarter.

"We were there for most of the game but then they hit those shots," Vasquez said. "Next time, we've got to do a better job of running out at them on the line."

"We're going through a tough time right now but I think eventually this team is going to click."

Ross, who scored all 11 of his points in the fourth quarter, including a trio of 3, said he feels good in the role of coming off the bench to begin this season after starting 61 games a year ago.

"I feel comfortable in it," Ross said. "It helps me relax and see what I have to do. I like it."

Milwaukee guard Michael Carter-Williams, who had 12 points and a game-high seven assists, said the more-seasoned Raptors took advantage of his young team's lapse to blow the game wide open.

"They went on a run, we didn't get out on their shooters and they made us pay," Carter-Williams said. "We can't fall asleep and a few times we fell asleep and they made us pay."

NOTES: Bucks G Greivis Vasquez spent the previous two seasons with the Raptors, appearing in 143 games and averaging 9.5 points, 3.7 assists and 2.5 rebounds per game. ... Based on opening-night rosters, the Bucks are the second youngest team in the NBA this season at 24 years and 144 days, older than only the Philadelphia 76ers at 23 years and 66 days. ... Toronto plays 10 of its next 12 games on the road beginning Tuesday night in Dallas. ... Raptors G Kyle Lowry had his 1,500th assist with Toronto in Wednesday's season opener against Indiana, becoming the fifth player in team history to reach that mark with the club, joining Jose Calderon (3,770), Alvin Williams (1,791), Damon Stoudamire (1,761) and Vince Carter (1,553).