The Toronto Raptors rode their Game 7 buzzer-beating momentum all the way through the first 36 minutes of their first game in Milwaukee. Then the fourth quarter happened.

What had been a 7-to-10 point lead throughout evaporated as the club was outscored 17-32, going 5-for-22 from the field. Kawhi Leonard, who had been nothing short of savior in the Conference Semifinals, missed all three of his shots and took a seeming backseat approach down the stretch.

Still, on the back of Kyle Lowry's timely 3-pointers and 14 points in the final 12 minutes, the Raptors remained in position to steal one at Fiserv Forum. With about 3:10 to go, Toronto led 100-98. But it was all downhill from there. The Bucks went on a 10-0 run to keep Game 1 victories a delicacy in The Six.

After averaging 39.7 and 38.7 minutes in their previous series respectively, Leonard and Lowry both played over 40 minutes just two days later. And the Raptors needed every second, as Head Coach Nick Nurse found little time to rest his leaders.

Attributing a poor fourth quarter to fatigue is tricky, especially when Lowry was instrumental in keeping Toronto close as time ticked away. But there's no doubt some of Leonard's shots came off shorter than usual, the club vouched for more half-court sets, and outside of a few Pascal Siakam drives, the Raptors hovered around the 3-point line and high post. Their attack became completely perimeter-centric. Lowry kept them afloat by hitting bombs he doesn't even normally take.

Toronto could very easily come back on Friday and take what was rightfully theirs. They could make people like me into fools for even suggesting fatigue could be an issue going forward.

But are 30-point, 7-for-9 from deep, 40+ minute games from Lowry sustainable? Remember: he is averaging 13.8 on 25.6% from 3-point range these playoffs.

And without another signature Lowry game, the onus will be on Leonard and company to pick up what production he cannot duplicate. Can Kawhi gear up for another 42 minutes, nab eight rebounds, three steals, and 31 points on better efficiency?

While it seems foolish to doubt Kawhi, his supernova performances from the first four games of the Philadelphia series have tapered off. During that time, he was dropping in 38 points on 61.8% shooting and 46.4% from three. In the four games since, this has fallen to 30.5 on 41.6% shooting and 13.6% from deep.

Of course, the 76ers' stiffer game plan contorted these numbers, but his production against Milwaukee was right aligned with these decreased totals (31 points, 38.5 FG%, 20 3P%). It's probably a mix of increased focus on him and fatigue.

Could Leonard perform better on less minutes? This might be something the Raptors can't test.

During the postseason, Toronto is 15.2 points worse with Leonard off the floor, per basketball-reference. Those minutes without him have been abysmal since the Raptors have gotten little out of players not named Kawhi. Now, 40-minute games have become the protocol, even if Lowry is scoring his most points in a playoff game since 2016.

Meanwhile, as the Raptors are being pushed to their limits, the Bucks have enjoyed a relatively relaxed playoff push. Playing three fewer games than Toronto, Milwaukee has also had the luxury of featuring Giannis Antetokounmpo – a frontrunner for the MVP award – only 32 minutes per game. Although they needed 37 from him on Wednesday, the Greek Freak has yet to cross the 40-minute threshold this postseason.

What's more, the Bucks have continued outscoring opponents throughout the playoffs with Giannis on the bench. They're plus-11 when he sits (plus-2.2 if you discount their Detroit series). And when he's on the floor, they are shellacking the opposition by 17 (+12.5 discounting Detroit).

This means the Bucks remain productive even if their best player is on the pine, while the Raptors disintegrate. And when Antetokunmpo and Leonard share the floor, Giannis will have far less mileage on his legs than his counterpart.

Toronto faced a mirrored effect with Philly's Joel Embiid last round. When The Process sat in these playoffs, the Sixers were 20.9 points worse. With Milwaukee, the Raptors face an overall less talented starting lineup, but they will see a barrage of production regardless of who takes the floor – something they have not yet seen this postseason.

To reach their ultimate destination, the NBA Finals, the Raptors require ironman performances. For a team full of gritty veterans and a budding star in Siakam, actually playing these minutes isn't the issue. A problem emerges only when you compare these long nights to the short days' work their opponents have and may continue to enjoy.

When one player is on minute-40, and the guy across from them is just crossing the 33 mark, it's obvious who has the advantage in crunch-time.