Harlequins have started the search to replace Jack Clifford following the announcement that the England international back-row has been forced to retire with a shoulder injury.
Paul Gustard will be looking for a replacement as soon as possible, and have already been linked with a number of players.
Here, we look at five potential targets for Quins:
1. Mark Wilson
The 17-cap England flanker is back at Newcastle Falcons following an unsuccessful loan spell with Sale Sharks. If Wilson is to play a role in the Six Nations/Autumn Internationals, the 30-year-old could do with a few games to tune himself up. Therefore, a loan move to the Stoop would make perfect sense,
2. Jacques du Plessis
Harlequins have now made a move for the versatile South African powerhouse from Montpellier, according to The Rugby Paper. Du Plessis is reportedly also in talks with wasps, with our sources suggesting the 27-yr old would prefer a move to London.
3. Callum Gibbins
The former Glasgow captain was called the "perfect Warrior" after his departure was confirmed last month. He spent three seasons at Scotstoun since arriving from Hurricanes in his native New Zealand and made 46 appearances. The 31-year-old would be the perfect replacement.
4. John Barclay
After failing to find a new club, the flanker announced his retirement from rugby union last week; drawing the curtain on a 16-year career. However, he is still a terrific player and it would be interesting to see if Harlequins could persuade him to sign a short-term deal to help out Quins.
5. David Pocock
He is another player that has not given any details about his future, and at 31, he may still have more miles in the clock. However, this was the final season of his contract with the Panasonic Wild Knights in Japan, and given the stress his body has been put under throughout his career, no one would blame the flanker for hanging up his boots early.