Sussex have confirmed that Stiaan van Zyl will stay at the club in 2021 despite the end of Kolpak registrations, fulfilling his contract on overseas terms, while David Wiese's time at Hove is set to come to an end.

Van Zyl, who signed a three-year extension in early 2019 after initially joining the club in 2017, missed the 2020 county season due to restrictions on international travel and club finances, and it was mutually agreed that he would return as an overseas player next summer.

Wiese, the South African allrounder, has left the club at the end of his contract after four seasons as a Kolpak player, but a Sussex statement said that he could still return as an overseas player for the T20 Blast.

The ECB confirmed in writing to counties two weeks ago that Kolpak registrations would be invalid once the UK's transition period with the European Union comes to an end on December 31, with affected players either leaving their clubs or re-signing as overseas players. Players with settled or pre-settled status in the UK through EU citizenship will be free to continue playing as locals.

Counties will be allowed to field two overseas players in all formats next season, having previously been permitted only one in the County Championship and Royal London Cup.

Travis Head, the Australia batsman, is due to be Sussex's second main overseas player after having his contract for this summer deferred to 2021, but it remains to be seen which formats he will play. With Rashid Khan, whose contract was cancelled this year to allow him to play in the CPL and the IPL, also under consideration for a T20-only deal, it could be that van Zyl and Head only play in the County Championship and the Royal London One-Day Cup.

"Obviously the government is kicking us out of here with Brexit at this stage, and I suppose the joy-ride had to come to an end at some stage," Wiese joked after Sussex's Blast quarter-final defeat to Lancashire last week. "It's been a good couple of years for me, and hopefully it's not the end.

"I could come back as an overseas - obviously it's trying times financially, a lot of the clubs are in tough positions and there are contracts in place with other players, so we'll have to see what the future holds. I'll go back home, chill out with a bit of family time and hopefully things work out in the future that I can come back here."

Wiese is the latest Sussex player to depart in a period of transition for the club. Luke Wells and Harry Finch will both be released at the end of their contracts, while Danny Briggs has signed for Warwickshire and Laurie Evans spent the season on loan at Surrey ahead of a permanent move. George Garton, Tom Haines and Delray Rawlins have all signed new deals.

Meanwhile, head coach Jason Gillespie has returned home to take up the South Australia job, with the club not expected to recruit a replacement until the start of next year. Assistant coaches James Kirtley, Ian Salisbury and Jason Swift are all likely to be candidates.

Matt Roller is an assistant editor at ESPNcricinfo. He tweets at @mroller98