Nemanja Matic is not used to being in the spotlight but his barnstorming home debut for Manchester United on Sunday only underlined the folly of Chelsea's decision to allow him to move to Old Trafford.
The Premier League has only just begun but United's decisive summer transfer window manifested itself in an emphatic 4-0 win over West Ham, just 24 hours after the weakened reigning champions slumped to a shock 3-2 loss to Burnley at Stamford Bridge.
Matic was a star performer at Old Trafford. The 29-year-old left Chelsea to be reunited with former manager Jose Mourinho and, unsurprisingly, immediately looked right at home playing under a familiar face, bringing balance, calm and power to his new side's midfield.
Considered slow, unfashionable and uncharismatic - Matic wasn't the most marketable player in west London but he is a player that Antonio Conte always respected.
Indeed, the Chelsea manager fought hard - and successfully - to keep Matic in his first season at the club in the face of interest from Juventus and the ex-Benfica man forged a fine partnership with N'Golo Kante to help his side win the title.
Kante rightfully swept up the Player of the Season awards but football is a team game and Matic always elevates the performances of those alongside him.
Many great players have benefitted from his industry and intelligence: Cesc Fabregas, Kante and now Paul Pogba.
Chelsea could have sold Matic to Juve, who made an approach again this summer, but they would have got less than the £40m that United offered and the transfer to Old Trafford was also a more lucrative move for the Serbian from a personal perspective.
He had less than two years to run on his Chelsea deal and, with several clubs interested, he was in a strong bargaining position.
Matic boosted his wage by £50,000-a-week in accepting the chance to work with Mourinho again. It is clear that although Chelsea rated him, they didn't think he was worth quite that much.
Mourinho thought it would be "impossible" to sign Matic from Chelsea but he now seems delighted - and surprised - that he got his man.
"I always thought he could be a perfect player for us but I didn't disturb him, I didn't disturb Chelsea nd I never thought it was possible unless something special was happening," the former Blues boss explained.
"And it looked like something was happening. Because his agent told me 'You can have him; you just have to pay.'
"So we have him, and we are very happy with that."
Chelsea, for their part, felt that Cesc Fabregas was the in-demand midfielder worth keeping - not Matic.
The Spaniard drew interest from AC Milan during the summer but the Blues opted instead to discarded Matic, leaving him to train alone in pre-season.
Matic is now on more money than Kante and Chelsea have reinvested his transfer fee in Tiemoue Bakayoko. The former Monaco man is Conte's perfect midfielder as he has the power and athleticism to work in a midfield two with Kante.
However, an unfortunately timed knee injury means he is currently unavailable for selection and even when he is fit, he will need more time to adapt to his new surroundings.
Furthermore, even with Bakayoko, Chelsea look short on numbers and quality in midfield, particularly now that Fabregas will have sit out next week's away game against Tottenham through suspension, after being dismissed against Burnley.
David Luiz, Andreas Christensen or Kyle Scott are now Conte's uninspiring options for the trip to Wembley, unless Chelsea make a signing before the end of the week.
Certainly, £40m was a good fee for Matic but Chelsea have invested their money in young players without Premier League experience, taking a step backwards in the hope of taking two forward.
They may have replaced Matic but they have sold a whole host of other talent and face a scramble to bring in more players before the transfer window closes on August 31. The Blues may be held to ransom in the market as their lack of numbers is well known across Europe.
The new television deal makes English clubs are rich enough to say "no" to even the biggest clubs, while foreign sides will do everything in their power to get a slice of Chelsea's riches.
The Blues have watched Man United, along with Manchester City, be decisive at securing their targets this summer but they still have time to make amends before the window shuts.
The reality is, though, is that they have already allowed United to steal a march on them in what promises to be a far more competitive title race this season - and they only have themselves to blame for for Matic's inevitable impact this season.