Zverev reached a career high second in the world rankings before dropping to 12th following his injuryGermany's Alexander Zverev returned to action after six months out with an ankle injury at the Diriyah Tennis Cup exhibition in Saudi Arabia on Thursday.
On his return he beat Dominic Thiem before losing to 2021 US Open champion Daniil Medvedev 6-4 6-0.
British number one Cameron Norrie reached the semi-finals by beating Greek top seed Stefanos Tsitsipas.
The world number 14, who earlier defeated Australian Nick Kyrgios, won 6-4 6-4.
Zverev will play Stan Wawrinka in the last four after the Swiss beat Russia's Andrey Rublev.
Zverev had planned to return at the Davis Cup in September but withdrew because he was experiencing "extreme pain".
The Olympic champion left court in a wheelchair after his injury in Paris.
