Former Pompey wanted man at centre of £15m transfer tussle between West Ham, Everton and Borussia Dortmund

The emerging centre-back was linked with a January transfer window deadline-day move to Fratton Park in 2023. The Blues were reportedly joined by Bristol City and Wycombe Wanderers in the race to sign the exciting Irishman, who was making huge waves on loan at Belgian outfit RWD Molenbeek while on loan from Crystal Palace.

Pompey went on to sign Di’Shon Bernard from Manchester United on loan as they turned their attentions away from O’Brien during John Mousinho’s first transfer window as head coach.

Yet they clearly missed an opportunity, with the now Republic of Ireland international in hot demand this summer following his impressive appearances with Lyon in Ligue 1.

West Ham and Everton are both keen to bring the defender back to the Premier League for a significantly higher fee than the £850,000 the French side forked out last summer. Meanwhile, beaten Champions League finalists Borussia Dortmund are also reportedly in the hunt for the 23-year-old’s signature after they said goodbye to Mats Hummels at the end of the season.

Following his move from Palace 12 months ago, O’Brien featured 32 times for Lyon as they finished sixth in the French top-flight and lost to PSG in the Coupe de France final. O’Brien, who also made his Ireland debut last season, scored in that game to take his goal tally to the season to five.

If the Premier League duo or Dortmund make moves for the now £15m-rated defender, Palace could land a significant cash windfall as they inserted a 25-per-cent sell-on clause in the Cork man’s Lyon deal.

With Bernard and fellow centre-back Ryley Towler added to the Blues’ ranks in January 2023, Pompey went on to finish their 2022-23 League One season in eighth place.

The Blues, under the leadership of sporting director Rich Hughes, added further central defensive reinforcements to their ranks last summer in the form of Conor Shaughnessy and Regan Poole. A January move for Tom McIntyre was also completed last January as the squad assembled by Hughes and Mousinho finished the 2023-24 season as League One champions.

Missing out on someone of O’Brien’s calibre will be regretful - but it once again showcases Hughes’ eye for emerging talent, with the Irishman set to hand Lyon a handsome profit this transfer window.

Incidentally, Bernard is now available on a free transfer following the expiry of his Sheffield Wednesday contract. The defender impressed during his time at Fratton Park, making 10 league appearances over the second half of the 2022-23 season.