Sunderland were said to be 'stepping up' their bid for the right-back.
Rumoured Sunderland target Jason Naismith has signed for Peterborough United.
The Sun on Sunday claimed Sunderland were 'stepping up a bid' for the 23-year-old - who played under the new Mackems manager Jack Ross at St Mirren - and were looking to offload players ahead of a '£200,000' move.
However, it is Peterborough who have won the race for his services - although, according to Posh owner Darragh MacAntony, a 'massive EFL club' did come close to derailing the deal.
Posting on Twitter on Tuesday evening, MacAnthony wrote:
BIG SIGNING - Delighted to announce signing of one of the best Right Backs in the SPL 23 year old Jason Naismith from Ross County for a 6 figure fee on 3 year contract. Very exciting addition to the squad at @theposhofficial— Darragh MacAnthony (@DMAC102) 12 June 2018
We nearly did today. Big well done to Barry & @Liz_Elsom who worked on this since 8am this morning as a massive club in EFL made this one a near miss but we got there late this evening to get it done. https://t.co/tjCl2eLcUD— Darragh MacAnthony (@DMAC102) 12 June 2018
Yes our only choice since May recruitment meeting :)) but didnt think we would get him so went for another RB but then resurrected this deal somehow. Amazed we signed him if im honest. https://t.co/OTTsRbp0bh— Darragh MacAnthony (@DMAC102) 12 June 2018
Naismith impressed despite Ross County's relegation last season, attracting interest from Aberdeen, Burton Albion and Plymouth, according to the Daily Record.
And the signing looks even more impressive for Peterborough, with MacAnthony suggesting the Cambridgeshire side have a future Scotland right-back on their hands.
Thats what current Scotland manager intimated to us Yep https://t.co/jAW3SD3zv9— Darragh MacAnthony (@DMAC102) 12 June 2018
Sunderland released their long-serving right-back Billy Jones last week, but still have Donald Love and Adam Matthews on the books in his position.