Record fee likely as Celtic consider life without O'Riley
Speculation about Matt O'Riley's future has been a daily constant in Scotland's media all summer after the midfielder helped Celtic to the league title and Scottish Cup double.
Since Atletico Madrid had an approach rejected in January, it has seemed like only a matter of time before somebody matched Celtic's valuation for the elegantly influential 23-year-old.
This summer, it has been Atalanta and, most recently, Brighton & Hove Albion, who have been most strongly linked with the London-born Denmark international.
So what has brought him to the brink of a move to the Premier League and how might his departure affect Celtic and any future employer?
Who is Matt O'Riley?
A native of Hounslow, O'Riley joined Fulham's academy at the age of eight, graduating to a first-team debut as a 16-year-old in an EFL Cup win away to Wycombe Wanderers.
However, having made just five appearances, and only one in the league as a substitute, in the three years thereafter, the England youth international rejected the offer of a new contract and joined MK Dons in League One.
With 10 goals in 54 appearances, nearly all of them starts, O'Riley had already shown his goal threat from midfield.
Those performances persuaded Celtic to shell out a reported £1.5m in January 2022 to match his release clause.
Eligible to represent Denmark and Norway due to his mother's side of the family, it only took three months starring in the Premiership for O'Riley to be called up to Denmark Under-21s.
Four years on and he has accumulated three league winners' medals, two for the Scottish Cup and one for the League Cup as well as vital experience on the European club stage.
What would O'Riley exit mean for Celtic?
O'Riley's statistics are hugely impressive.
Since arriving at Celtic, he has provided more assists than anyone in the Scottish Premiership, his 29 being six more than Rangers captain James Tavernier.
O'Riley ranks third when combining goals and assists, his 54 involvements only two behind Heart of Midlothian striker Lawrence Shankland and seven adrift of Tavernier, king of Rangers penalties.
O'Riley (217) is second only to Tavernier (275) and well ahead of next best, Kilmarnock winger Danny Armstrong (173) in terms of chances created - and only 10 behind the Rangers man when you only count those from open play.
As for touches in the box, O'Riley outshines any Premiership player, his 555 being more than Shankland's 498 and well ahead of team-mate Daizen Maeda and Bojan Miovski, the striker sold this month by Aberdeen to Girona.
O'Riley is also fourth best for successful crosses behind Tavernier, Armstrong and former Rangers left-back Borna Barisic - and his 25 goals over the last two years is only bettered by four strikers and that man Tavernier.
Those steadily improving statistics mean O'Riley has possibly now overtaken captain Callum McGregor and Japan's Reo Hatate in terms of importance to Celtic.
The trio have been central to a scintillating start to this season for Brendan Rodgers' side.
Acknowledging their role last week, the manager said: "In my history as a coach, the dynamic midfield three is always important.
"It's never about one player, it's always about the three. And I think that it was probably only into the latter stages of last season that those three came together.
"And I think you've seen the flow and the dynamism and how it all makes the team function."
Rodgers has repeatedly said he doesn't want to lose O'Riley, while praising the player's "phenomenal mentality" in blocking out the speculation.
Seeking to bolster his squad ahead of the Champions League, Rodgers is not reliant on funds from any sale of O'Riley.
"I still think we need another player in that position," he said. "If he was to go, we'd need two more."
Rodgers has said he doubts whether he could "replace like-for-like" and Celtic would not pay such "big money" on one player.
It looks increasingly likely that it will take an offer north of the club's £25m record sales for both Kieran Tierney and Jota to prise O'Riley away.
What would O'Riley arrival mean for Brighton?
O'Riley will have been disappointed to have missed out on the Denmark squad for this summer's Euro 2024 finals.
After handing him a start in their 2-0 qualifying defeat by Northern Ireland in Belfast, then head coach Kasper Hjulmand explained in March that he thought O'Riley had six better midfielders ahead of him.
O'Riley will perhaps think he has a better chance of adding to his two caps now that former Celtic midfielder Morten Wieghorst has been appointed caretaker, but playing regularly in one of the top leagues would no doubt help his cause.
Europa League winners Atalanta had appeared to be favourites for his signature, but after reportedly failing with a series of bids, the Serie A club on Sunday signed Serbia international Lazar Samardzic from Udinese.
Unlike the Italians - and Celtic - Brighton cannot offer European football this season, but they have been investing heavily this summer under new head coach Fabian Hurzeler.
Pascal Gross has joined Borussia Dortmund, Adam Lallana moved to Southampton and fellow veteran James Milner started their season opener against Everton.
Despite an impressive 3-0 away win, the 31-year-old Hurzeler, who led St Pauli to promotion to the Budesliga before becoming the youngest permanent head coach in Premier League history, may want more youthful legs in that central area of the park.
He has already signed defensive midfielder Mats Wieffer from Feyenoord. O'Riley, his languid running style being somewhat deceiving given his qualities as a constantly involved, pivotal all-rounder, could be next on the agenda.
With fans' favourite Billy Gilmour only given eight minutes as a late replacement for Milner, O'Riley's arrival could mean an exit for the 23-year-old Scotland midfielder, who is reportedly on Napoli's wanted list.
