'Why did Chelsea sell Nemanja Matic?' - how Manchester United reacted to deal

Manchester United got their second season under Jose Mourinho off to a flying start on Sunday with a near-perfect 4-0 win over West Ham.

A brace from £75million marquee signing Romelu Lukaku, who continues to plight the Hammers scoring his 10th and 11th goals against them in just 13 games, gave the hosts a comfortable lead before two late goals from French duo Anthony Martial and Paul Pogba rounded things off in style.

While Lukaku took the headlines, another new signing was also winning over new fans as former Chelsea midfielder Nemanja Matic walked away with the Man of the Match award on his Old Trafford debut.

The Serbian, who left Stamford Bridge for a reunion with Mourinho for a fee of £40m in July, already looks to be justifying his price tag with his dominant midfield performance allowing those further forward to devastate Slaven Bilic’s side.

Despite the champions having brought in Tiemoue Bakayoko as a replacement, many are still shocked by the Blues’ decision to let the 29-year-old join their title rivals.

Plenty of Manchester United heroes past and present have expressed their delight at the signing, although Paul Ince is yet to be convinced...

“It depends on what was happening behind doors [at Chelsea], of course with Chelsea [they have] the money, but I know that I brought him to Stamford Bridge because I thought he was a player with special qualities and since I left I always felt he could be a perfect player for us," he told reporters.

“But I didn’t disturb him, or Chelsea. I didn’t think it was possible unless something special was happening, and it looks like something was happening because his agent said we could have him, we would just have to pay.”

“It’s a strange one for Chelsea to let him go because I thought he was good for them with Kante and I think they need to strengthen,” Neville told Sky Sports.

"So I'm not quite sure why they're letting him go but they must have replacements lined up."

“I really like the Matic signing, that was the one that surprised me a little bit,” said the former midfielder when speaking to BT Sport.

“It makes you wonder ‘why did Chelsea sell him?’ I think he brings aggression to United’s midfield, which is something they have been lacking.”

"I was a little bit surprised by the fact Chelsea are selling to their rivals who will be challenging for the Premier league next year,” Irwin told talkSport.

"But Matic has done a fantastic job for Chelsea over the last few years and I suppose it was a bit of a thank you [to let him join Manchester United].”

"Actually I am [surprised]. But at the same time I am very happy that we have got him.”

"Some people have said that they can’t believe Chelsea let Matic go to United, and that they’ve handed them the title, but I don’t see that," he told Paddy Power.

"Towards the back end of last season, he couldn’t get in their team.

"So I don’t think he’ll be a huge loss to them, but he’s still a very good player to sit in front of the back four, do the simple things, pass the ball - he’s good at what he does."