MANCHESTER, England — As Nemanja Matic was winning towering headers, intercepting passes, dribbling round opponents and generally running the midfield in his first Premier League game for Manchester United, imagine what Antonio Conte must have been thinking.
The Chelsea coach didn't want to sell Matic, particularly not to a title rival like United. But an offer of 40 million pounds ($53 million) for a 29-year-old was too good for Chelsea's hierarchy to turn down.
It could prove to be one of the most pivotal pieces of business done in the off-season.
Romelu Lukaku stole the spotlight in United's 4-0 win over West Ham on Sunday, scoring two goals, but it was Matic — a player costing around half as much this summer — who was the key to the performance.
He dominated Old Trafford in his first match there as a United player, looking every inch the holding midfielder the team needs with Michael Carrick nearing the end of his time at the club.
"He is a player I call a stability player," Mourinho said of Matic.
He was more than that against West Ham. In a man-of-the-match display, he made more passes (69) and covered more distance (11.41 kilometres) than anybody else on the field, while he won more tackles and had more touches (89) than any other United player.
One minute Matic was beating three players with sublime skill and racing down the right touchline. The next he was scooping a pass, Karel Poborsky-style, to Paul Pogba to set up another attack.
He won big headers from goal kicks and long clearances by West Ham, and read the game masterfully. Eric Bailly and Phil Jones, United's centre backs, generally cruised through the 90 minutes with Matic in front of them.
Crucially, and as has been widely predicted, Matic's presence allowed Pogba more freedom to roam forward in central midfield. With strikers Lukaku and Marcus Rashford stretching play with their runs and Pogba making the most of the space behind, United was so much more dangerous.
Pogba scored the fourth goal from 25 metres out in the 90th minute. He hit the goal frame (10 times) more often than scoring (nine goals) last season, but this season could be different — and he could have Matic largely to thank.
Mourinho cannot believe his luck that Matic is his player again, having brought the Serbia international to Chelsea from Benfica in 2014.
Asked if it was a surprise that Chelsea sold Matic to United, Mourinho said: "It depends on what is happening, or what was happening behind doors. I don't know. Only thing I know is that, of course, with Chelsea money, I brought him to Stamford Bridge because I thought he was a player with special qualities. And since I left, I always thought he could be a perfect player for us.
"But I didn't disturb him, I didn't disturb Chelsea. I never thought it was possible unless something special was happening, 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. He is a player that our team needs."
Chelsea needs him, too, at the moment.
Conte is short on numbers after a frustrating summer in the transfer market. Tiemoue Bakayoko was signed from Monaco, to complement Matic rather than replace him. Bakayoko is currently out injured, leaving Chelsea with Cesc Fabregas and N'Golo Kante as central midfielders.
And Fabregas is now banned after his sending-off in Chelsea's 3-2 loss to Burnley on Saturday.
"My idea was to give Bakayoko the right time to adapt in this league behind Matic," Conte said. "But now after the sale of Matic, we need to try to accelerate this process for Bakayokoafter his injury."
Conte described the departure of Matic as a "great loss" to Chelsea and has said it was a boardroom decision.
"Sometimes you must accept this crazy transfer market," he said.
Spending 40 million pounds on a 29-year-old defensive midfielder doesn't sound like sensible business, but the arrival of Matic has knitted things together perfectly so far for United.
It could be the transfer that tips the battle for the Premier League title United's way.
Steve Douglas is at www.twitter.com/sdouglas80