Peter Siddle has withdrawn from his Nottinghamshire contract for 2017 due to a persistent back injury. Siddle, 32, has not played since the Hobart Test against South Africa in November, during which he suffered a recurrence of the back problem that had kept him out for much of the previous year.
Notts have been linked with potentially signing Siddle's Victoria team-mate and fellow Australia international James Pattinson, with Mick Newell, the club's director of cricket, hopeful of "quickly securing a replacement".
Siddle, who played for Notts in 2014 and Lancashire the following season, had signed a two-year deal to return to Trent Bridge but was unable to appear in 2016 due to stress fractures in his back. He made a comeback at the start of the 2016-17 season with Victoria and won a Test recall against South Africa before being sidelined once again.
"I guess the years of playing cricket, you always have little setbacks with injury and missing cricket at different stages," Siddle said. "It makes it a little bit easier to take in when you get older. So, I've been able to stay pretty level.
"I don't think I've played this little cricket in an 18-month window since I was an 11-year-old kid and was just starting out. That's the most frustrating thing, not playing the game that you love and your profession. But mentally I'm pretty good. I'm in a good place and I've got some good people around me who give me good support."
Notts have already signed another Australian, Dan Christian, for the NatWest Blast but the arrival of James Pattinson - whose older brother, Darren, played for the county between 2008 and 2012 - would be a significant coup. Pattinson has taken 70 wickets in 17 Tests but missed out on a call-up to Australia's tour of India after Mitchell Starc was ruled out by injury, despite taking a five-wicket haul last week to help put Victoria in the Sheffield Shield final.
Newell said: "I feel for Peter in particular because he's had absolutely no luck in recent years when it comes to injuries. We certainly didn't imagine, when we signed him on a two-year contract for 2016 and 2017, that he wouldn't play a single game for us during that time. It's disappointing because his competitive character and proven ability would have been a real asset for us.
"We never stop monitoring the situation overseas. We're always looking at who is available and who has the kind of quality we need, so we're confident of quickly securing a replacement."