BARNSLEY are targeting a move for Leeds United defender Aapo Halme as they eye a second central defensive recruit in the space of 24 hours.
The Reds completed a deal to sign Sibbick on Tuesday night for an undisclosed six-figure fee, with the club in the market for central defenders after the decision to sell Ethan Pinnock to Brentford for £3m after the 26-year-old turned down the offer of a contract extension which would have made him Barnsley's highest earner.
Barnsley are now lining up a separate move for Leeds's Finnish stopper Halme.
Giant 6ft 5in defender Halme, 21, played five times for Leeds last term, having joined for £500,000 from HJK Helsinki in January 2018.
Highly-rated Sibbick made 31 appearances in all competitions for the Dons last season, netting the fourth goal in their shock FA Cup win over West Ham in January.
The Isleworth-born player, who has signed a four-year deal, is able to operate at centre-half and right-back.
On the sale of Sibbick, Dons boss Wally Downes said: “I would have liked to have kept Toby, but we felt we couldn’t stand in his way after the bid came in.
"The fee will help us to increase the playing budget so it suits us, but it also suits Barnsley and the player.
"Toby was a big part of what we did last season. He scored the goal that made us all breathe a sigh of relief against West Ham and the team’s performances after that showed what we could do.
"In a way his goal against West Ham kick-started us, it gave us belief that we could stay up, and Toby’s performances caught the eye."
Sibbick's arrival follows on from the additions of Mike-Steven Bahre, Luke Thomas, Bradley Collins, Mads Juel Andersen and Samuel Radlinger, with the club in the market for several other targets.
On the outgoing front, two of last season's promotion heroes in Adam Davies and Liam Lindsay have joined Championship rivals Stoke City, with Pinnock linking up with Brentford.