Chelsea are willing to offer Levi Colwill to Brighton in part-exchange for Marc Cucurella, according to reports.
Cucurella has been heavily linked with Manchester City this summer, but the Premier League champions have withdrawn their interest.
Pep Guardiola's side are on the lookout for a replacement for Oleksandr Zinchenko, who has joined Arsenal.
But City were unwilling to meet Brighton's asking price of £50m, having already seen a bid of £30m turned down by the south coast side.
Cucurella could nevertheless be on his way out of the Amex Stadium, with Chelsea in pole position to sign him.
The Blues are hoping to reach an agreement with Brighton that could potentially send Colwill in the opposite direction.
The centre-back thrived on loan at Huddersfield last season but he is seen as expendable by Thomas Tuchel.
Colwill is a Chelsea academy graduate but he is ready to move on permanently unless he is guaranteed a certain amount of first-team football at Stamford Bridge.
That looks unlikely with Tuchel still pushing to sign at least two more defenders before the transfer window closes on September 1.
According to the Evening Standard, Chelsea are considering an offer of £30m plus Colwill, whom they value at £20m.
But it remains to be seen whether that would be sufficient to prise the Spaniard away from the Seagulls.
Cucurella was Brighton's Player of the Year last term and remains a key part of Graham Potter's plans.
The 24-year-old is under contract at the Amex until 2026 and Brighton are in no hurry to sell him.
Tuchel admires Cucurella and could potentially look to use him as a left-sided centre-back.
He would also provide competition for Ben Chilwell at left wing-back, with Marcos Alonso likely to depart if a deal for Cucurella is agreed.
Chelsea will begin the Premier League season against Everton at Goodison Park in the late kick-off on Saturday.
