Federer, who withdrew from his scheduled fourth-round match against Matteo Berrettini at Roland Garros at the weekend, is preparing for his fourth tournament of the year. The 103-time title winner claimed the Halle crown when the tournament was last played in 2019.
Federer boasts 19 tour-level titles on grass and a 187-27 match record, for an Open-Era-leading winning percentage of 87.4% on the surface.
Explaining his decision to withdraw from Roland Garros, Federer last Sunday tweeted: “After discussions with my team, I’ve decided I will need to pull out of Roland Garros today. After two knee surgeries and over a year of rehabilitation, it’s important that I listen to my body and make sure I don’t push myself too quickly on my road to recovery. I am thrilled to have gotten three matches under my belt. There is no greater feeling than being back on court.”