The Toronto Raptors clinched their first-round NBA playoff series against the Milwaukee Bucks but not before almost suffering an historic collapse having blown a 25-point lead.

With Thursday's 92-89 game-six victory, the Raptors won the Eastern Conference series 4-2. They face defending champions the Cleveland Cavaliers in the semi-finals.

Yet the Raptors flirted with disaster at Milwaukee's BMO Harris Bradley Center. After holding a commanding 72-48 lead with less than four minutes remaining in the third quarter, Toronto fell apart. The Bucks finished the third quarter on a 13-2 run.

And the Bucks continued their furious comeback for most of the fourth quarter. Jason Terry's 27-foot three-pointer at the 3:05 mark gave the Bucks an 80-78 lead as Milwaukee's arena erupted in noise. 

The Cavaliers made history last week by overcoming a 25-point half-time lead to stun the Indiana Pacers; Toronto appeared on the verge of blowing a 24-point lead in the final 15 minutes. But the Raptors snapped out of their stupor in the final few minutes, with DeMar DeRozan taking charge thanks to his 32 points. 

Giannis Antetokounmpo scored 34 points and collected nine rebounds to almost lead the Bucks to a comeback for the ages against the Raptors. His most amazing number: he played 47 minutes.

In Memphis, the Spurs rallied from a seven-point deficit in the final six minutes to beat the Grizzlies 103-96 and win their series 4-2. 

While Kawhi Leonard was his usual stat beast (29 points and nine rebounds), veteran guard Tony Parker proved the difference down the stretch for the Spurs, finishing with 27 points on 11-of-14 shooting.

Spurs centre Pau Gasol missed all six shots he took and turned the ball over twice but LaMarcus Aldridge had 17 points and 12 rebounds as San Antonio look ahead to a Western Conference semi-final showdown with the Houston Rockets.

Mike Conley led the Grizzlies with 26 points, while Marc Gasol contributed 18 of his own.