Atlantic Avenue in Delray Beach is all abuzz as the 2021 Delray Beach Open gets underway this week.

Originally scheduled for February, the 2021 Delray Beach Open by VITACOST.com began Monday.

The 28-player field for the annual tennis tournament is headlined by three past champions: Reilly Opelka (2020), Frances Tiafoe (2018) and Sam Querrey (2017).

American John Isner, a Wimbledon semifinalist in 2018, will be making his eighth appearance at the tournament.

Three-time Grand Slam title winner Andy Murray announced last week he was pulling out of the Delray Beach Open to minimize his risks of contracting COVID-19 ahead of the Australian Open.

ATP 250 qualifying matches will take place Tuesday and Wednesday.

The ATP Champions Tour legends event, featuring past-main draw champion Tommy Haas and six-time doubles champions Bob and Mike Bryan, occurs through Wednesday.

Attendance for each session at the tournament will be capped at 2,000 people, just under 25 percent of the outdoor stadium's total capacity.

"We had to take back any ticket sales that had been made and start from scratch and resale for this new date. … Whoever ends up here, ends up here," said John Butler, executive director of the Delray Beach Open.

Shops and restaurant owners along Atlantic Avenue are eager to see the boost in foot traffic from fans visiting for the tournament.

"We want people to be out and having fun and be engaged with each other. We’ve had to kind of scale that back," said Craig O’Keefe, director of operations at Lionfish Delray Beach.

The tournament concludes Jan. 13 with the doubles and singles finals.

Click here for a schedule of events and tickets.