Playing on a single site away from fans in a quarantine setting, teams in the National Basketball Association face plenty of unknowns as the league restarts its season this week.

At least one thing, however, is not in doubt — the Milwaukee Bucks own the Eastern Conference.

One of the league's top scorers and rebounders, forward Giannis Antetokounmpo has waged an MVP campaign with only one clear rival — Los Angeles Lakers star LeBron James — headlining a Bucks roster that entered the COVID-19 hiatus with a 53-12 record, atop the conference standings.

The 25-year-old took a hard fall during a March matchup against the Lakers, but what was feared to be a major knee injury proved only a minor joint-capsule strain.

"I believe in my technique. I worked extremely hard these four months we didn't play, and I just want to get back in shape and I think I'm fine," Antetokounmpo told reporters inside the Walt Disney World "bubble."

Still, the Bucks' path is not without challenges.

"Even though the Bucks, with the number one overall seed in the NBA — if people are going to question whether they can win at all, it ain’t about Giannis’ greatness, it’s about who is second and who is third," Jalen Rose, an ESPN analyst and former player, told reporters. "I see them potentially being vulnerable in the East to a couple of teams."

The reigning champion Toronto Raptors had the second-best record in the Eastern Conference as the NBA went on hiatus, despite losing Kawhi Leonard to the Los Angeles Clippers in the offseason, fending off speculation that the franchise would implode without the star forward.

The Boston Celtics, 43-21 in pre-COVID play, have enjoyed the spoils of 22-year-old forward Jayson Tatum's breakout year but will need guard Kemba Walker, who has struggled with knee issues.

With guard Eric Bledsoe rejoining the Bucks last week after being cleared from a prior coronavirus positive, Milwaukee's horizon looks even brighter.

"Eric looked great," said Bucks coach Mike Budenholzer. "In all honesty considering, you know, it's been a while since he's been able to touch the ball or do anything, he was very good."

Of course, with a grueling turnaround from quarantine and a tight playing schedule, success inside NBA's bubble could come down to which team stays on its feet.