Cape Town - Springbok and Stormers star Pieter-Steph du Toit underwent a second procedure on Monday to drain blood caused by a hematoma in his upper leg, Netwerk24 reports.
Du Toit is likely be sidelined until May.
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The 2019 World Rugby Player of the Year first went under knife on Sunday after his side's 33-14 loss to the Blues at Newlands the previous day.
SuperSport.com reported on Sunday that the blindside flank underwent a scan after the game before a decision was made for him to go under the knife.
"We look forward to his recovery and to have him back. He is obviously a huge player for us. The plan was to rest him now (in any case)," Stormers coach John Dobson told Netwerk24 on Monday.
Local Super Rugby franchises have an agreement with SA Rugby to rest their top Springboks for three matches during the competition.
The Stormers are already without World Cup stars Siya Kolisi and Bongi Mbonambi, who were both injured in the opening round win over the Hurricanes at Newlands.
Bok skipper Kolisi is out for another few weeks with a knee injury, while hooker Mbonambi - who suffered a hamstring injury - is likely to miss the remainder of Super Rugby.
With Du Toit sidelined, his brother Johan, Ernst van Rhyn and Cobus Wiese are the contenders to take his No 7 jersey.
The Stormers have a bye this weekend, with their next match scheduled against the Sharks in Durban on March 14.
- Compiled by Herman Mostert