Updated

MIAMI (AP) By definition, Portland and Miami are not yet facing must-win games.

It may seem otherwise.

Down 2-1 in their respective series, the last thing either the Trail Blazers or the Heat will want is to head out on the road later this week facing elimination. So in a pair of Game 4s on Monday - Portland plays host to Golden State as their Western Conference semifinal resumes, while Miami will entertain the Toronto Raptors in their back-and-forth East semis matchup - the home teams will face plenty of pressure.

''This is competition at its highest,'' Heat coach Erik Spoelstra said.

The Miami-Toronto series has been extremely tight, with the Raptors outscoring the Heat so far 287-285. But it will have a much different look now, after a pair of MRI exams on Sunday sent both starting centers to the sidelines.

Toronto said it will be without Jonas Valanciunas for the rest of the series because of a sprained right ankle. Miami isn't sure how long it will be without Hassan Whiteside, who is listed as day-to-day with a sprained knee ligament.

''It's going to be small-ball with a smaller center,'' Toronto's Kyle Lowry said. ''It's going to be a fun game.''

And now the Raptors and Heat know who awaits: Cleveland finished off its sweep of Atlanta on Sunday, putting the Cavaliers back in the Eastern Conference finals for the second straight year.

Toronto won a road game on Saturday to take the lead in its series. Golden State will now need a road win to keep the lead in its series.

The Blazers got back into their matchup by taking Game 3 behind a 40-point effort from Damian Lillard. Portland became the first team to beat Golden State twice this season, and it's unknown if the Warriors will have MVP Stephen Curry back from his knee injury in time for Game 4.

A look at Monday's games:

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Raptors at Heat, Toronto leads 2-1. 8 p.m., TNT.

The Raptors could be leading this series 3-0 right now.

Then again, so could the Heat.

It's rare that such statements would make any simultaneous sense, but in this case they seem to apply. The game that Toronto lost in this series came in overtime, a contest where Lowry and his backcourt mate DeMar DeRozan combined to shoot 12 for 35. The games that Miami has lost so far were ones where the Heat wasted fourth-quarter leads, a seven-point edge in Game 2 and a six-point cushion in Game 3.

Now it's up to Miami to find a way at home to knot the series.

''It's a very competitive series,'' said Heat guard Dwyane Wade, who scored 38 points in Game 3. ''They're the second seed for a reason. Throughout this year they won 56 games. It's a good team and we went in and got one from them, they came in and got one from us. ... This going to be one of those tough series that's going to go down to the last minute.''

The Heat were down by 13 points when the Raptors lost Valanciunas in the third quarter of Game 3, then went on a spurt to take the lead. In the end, Lowry's 29 second-half points were too much for Miami.

''When he's in a zone like that ... you want to do something to help him stay in that zone,'' the Raptors' Patrick Patterson said.

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Warriors at Trail Blazers, Golden State leads 2-1. 10:30 p.m., TNT.

Losing streaks don't happen to the Warriors.

Golden State is 10-0 in the games that immediately follow losses this season, winning those by an average of 15.8 points. Put another way, when the Warriors are annoyed, they respond - and usually emphatically.

''All it means is that we won a home court game,'' Portland coach Terry Stotts said. ''It was important to win it and it's going to be a tough game on Monday. To me, it wasn't an explosive game but we kept grinding it out a little bit.''

It was more than a grind-out.

Besides Lillard's brilliant 40-point effort, Al-Farouq Aminu needed only nine shot attempts to score 23 points. The Blazers were 17 for 30 from 3-point range, yet still attacked enough to get to the line 29 times (making 23).

''We stepped it up,'' Lillard said.

If the Warriors get Curry back - he's listed as doubtful - then the emotional lift would be seismic. Plus, Golden State knows that taking a 3-1 lead back home would present them with a chance for not just a closeout opportunity in Game 5 but perhaps a nice bit of rest before facing either San Antonio or Oklahoma City in the West finals.

''We don't have the luxury of staying with a set rotation,'' Warriors coach Steve Kerr said. ''We have to read what's going on and play different people based on what we see and what we need, but that's all right. We've got a lot of players who can play and they've been ready to perform all year.''