Alcaraz is slated to face both Tomas Machac or Frances Tiafoe within the second spherical, after a bye.

Ruud will face both Giovanni Mpetshi Perricard or a qualifier in his first match.

Notable first-round matchups in Barcelona:

Arthur Fils vs Pablo Carreno Busta

Stan Wawrinka vs Alejandro Davidovich Fokina

Tomas Machac vs Frances Tiafoe

Zverev Prime Seed at Munich

Alexander Zverev will look to shake off a droop on house soil in Munich, because the 2018 champion options as the highest seed. He’ll face Alexandre Muller within the first spherical and will face sixth-seeded Jakub Mensik, the Miami champion, within the quarterfinals.

Zverev has gone stone-cold since reaching the Australian Open remaining in January, dropping seven of his final 13 matches.

Mensik, who faces wild card Jannik Hanfmann within the first spherical, will play his first tennis since elevating the trophy in Laborious Rock Stadium.

Mensik takes a 6-4 lifetime document on clay into his first match on the floor this season.

American Ben Shelton is the second seed.