Saracens are hopeful that Owen Farrell will be fit for Sunday's Heineken Champions Cup round-of-16 clash with the Ospreys.

Farrell limped off with an ankle injury in the 70th minute of Saturday's victory over Harlequins, but the England captain has made a rapid recovery.

"Owen took part in some of the training today (Wednesday), so we're relatively optimistic that he'll be available for this weekend," said director of rugby Mark McCall.

RECAP: https://www.hamhigh.co.uk/sport/23412546.gallagher-premiership-saracens-36-harlequins-24/

Farrell cried out in pain after rolling his left ankle while making a tackle close to Saracens' tryline at Tottenham Hotspur Stadium and hobbled off.

The 31-year-old fly-half had injured the same joint while on England duty in the final stage of the Six Nations, raising concerns that an aggravation might have caused more significant damage.

But McCall has put those fears to rest as Saracens return to the knockout phase of Europe's prestige club competition, which they last won in 2019, after a two-year hiatus due to their relegation from the Premiership.

"Owen didn't need a scan. He was much better on Sunday, Monday and Tuesday after the pain," McCall said.

"He trained today and as long as there's no reaction to that I'm sure he'll be OK.

"He's our captain and he played brilliantly on the weekend, led the team very well. So fingers crossed."

Saracens' England contingent also includes Maro Itoje, Jamie George, Mako Vunipola and Max Malins, but despite their involvement in the Six Nations and against Harlequins, McCall insists they are raring to go.

"They have been away for eight weeks, but they've always been superb at coming back to the club and chucking themselves into it," McCall said.

"We saw that against Harlequins last weekend when they all played well. They're all looking forward to playing in a quarter-final in Europe, which we haven't done for a while."

The Champions Cup is set to be overhauled from the existing format of two pools of 12 teams and McCall would favour a return to the old structure of groups of four teams.

"It was magnificent to be honest. You had to work incredibly hard to get out of your group and it was a real achievement to get out of your group," McCall said.

"It's probably not the same achievement to get into the last 16 now as it was to get into the quarter-finals all those years ago. I personally would prefer the old format."