Argentina's 27th seed David Nalbandian retired with an illness while trailing Lithuania's Richard Berankis 6-1, 6-0, 2-0 in the second round at the Australian Open on Thursday.
The nature of the illness was not immediately revealed, but Nalbandian was coming off a gruelling five-set win over Australian Lleyton Hewitt in almost five hours in Tuesday's opening round.
The Argentine veteran was cramping towards the end of his epic win over Hewitt, which finished in the early hours of Wednesday, and was never a force in the 95th-ranked Berankis.
Nalbandian, looking out of shape after an injury-hit 2010, had two months off the tour with a hamstring injury last year after missing nine months with hip surgery in 2009.
Berankis will now play Spanish seventh seed David Ferrer in the third round on Saturday.