Chelsea have entered into talks with Fiorentina over the purchase of Juan Cuadrado as the Premier League leaders prepare for the possible departure of Mohamed Salah or André Schürrle this month.

José Mourinho had entered the January window anticipating no major business, having declared his satisfaction with a squad who have lost only twice in all competitions this season and remain in the hunt for silverware on four fronts. Yet, while Chelsea have sanctioned a number of loan moves for fringe players away from the club, interest has emerged in Schürrle and Salah, two of their senior squad players, which could see either leave before the deadline on 2 February.

Chelsea had hoped to add a right-sided forward of established talent next summer and had made known to Fiorentina their interest in Cuadrado, one of the key players in Colombia’s fine 2014 World Cup campaign but whose form has been patchy in Serie A since.

They have moved in the past 48 hours to sound out Fiorentina over the possibility of bringing the deal forward by six months in the acceptance that a sale of Salah or Schürrle would necessitate the immediate purchase of a replacement.

The move is born of Roma’s increased desire to secure Salah, most likely on an loan deal with a view to a £12m transfer, with the Egypt winger having made only six Premier League starts since joining from Basel a year ago and having little future at Chelsea.

Inquiries from Wolfsburg and Borussia Dortmund for Schürrle will test Mourinho’s resolve to retain the World Cup winner, whose form has been rather hit and miss this season. If neither player leaves this month Chelsea will revert to the original plan and put interest in Cuadrado on hold until the summer.

The 26-year-old, a £17.6m signing from Udinese in the summer of 2013 and capped 37 times, is contracted until 2019. Talks between Chelsea and Fiorentina have quickly established Cuadrado’s £26.8m buyout clause would have to be triggered if a deal is to be concluded. The player was included in the starting lineup for Wednesday’s Coppa Italia tie against Atalanta and remains in their plans for the immediate future.

Cuadrado – quick, strong and skilful – would appear a natural fit on the right side of Chelsea’s attacking trident, with his credentials confirmed by his summer exploits in Brazil where, with James Rodríguez at his side, he contributed a goal against Japan and four assists.

It remains to be seen whether Schürrle, an £18m signing from Bayer Leverkusen 18 months ago and a player who has contributed useful cameos this season but denied a regular run in the first team, would be keen on returning to the Bundesliga with Wolfsburg, who would be willing to pay around £23m.

More appealing to Schürrle may be a move to Dortmund, though their interest is likely to crystallise in a summer bid once the future of their Germany winger Marco Reus has become clear. Chelsea have monitored Reus’s position but there are numerous suitors, making Cuadrado a more realistic target.

Thibaut Courtois has said Chelsea can win a clean sweep of European and domestic honours. “Myself, Costa, Filipe, Fàbregas and the rest of the team want to win trophies for Chelsea,” the goalkeeper said, listing the summer arrivals.

“That starts in the League Cup to the last game in the Champions League. We want to win everything. It will be difficult but I think we have the team to do it.”