Cape Town - The Sharks are sweating on the availability of captain Keegan Daniel and centre Tim Whitehead as they prepare to face the Golden Lions in a Currie Cup clash at Kings Park on Friday.Daniel was withdrawn shortly before their 32-30 home loss to Griquas last Friday evening due to a knee injury, while Whitehead injured his ribs in the loss to the men from Kimberley. Jacques Botes took over the captaincy in Daniel's absence.Forwards coach Brad Macleod-Henderson said they will know more on the extent of the injuries later on Monday.“He (Daniel) struggled a bit during the week and at captain’s practice it never went away so he had to pull out with a knee niggle that had been troubling him all week, but which he hoped would settle," Macleod-Henderson told the Sharks website."Unfortunately it didn’t settle down enough for him to play. We’re hoping it doesn’t keep him out. Hopefully it’s not a serious injury but we’ll see on Monday how he is.” The coach admitted that he wasn't happy with the performance on the day, even though they had led after 79 minutes only to see Griquas score after the hooter to sneak a win.“Our set-pieces weren’t great, they dominated us on the pick and go game, and we probably got outmuscled a bit, so, a very disappointing day at the office."The Sharks next host the Golden Lions at Kings Park on Friday (17:05 kick-off).