Diego Costa and Cesc Fabregas helped Chelsea win the transfer window... but it would've been great to see Xabi Alonso back in the Premier League

• The summer transfer window closed on Monday night
• Chelsea strengthened their squad and sold their unwanted players
• Diego Costa has helped fire Jose Mourinho's side to the top of the table
• Danny Welbeck has a point to prove after leaving Manchester United 
• The 23-year-old joined Arsenal in a £16million deadline day deal
• Hull have made some inspired signings, including Hatem Ben Arfa on loan
• Sandro will give QPR a strong presence in central midfield
• Xabi Alonso and Toni Kroos would've been great additions to the Premier League but both moved elsewhere 

With the transfer window firmly closed until January, Premier League clubs up and down the land have a few months to reflect on their summer business.

But which sides had a window to remember? Who surprised their rivals with some wise acquisitions? And which players who chose to go elsewhere would've been the biggest asset to England's top-flight?

We asked our three wise men - Jamie Carragher, Martin Keown and Jamie Redknapp - those questions and more. Here's what they had to say.

Which team 'won' the transfer window?

JAMIE CARRAGHER: Chelsea, without a doubt. They got most of their business done early and always seemed to be in control. The way Diego Costa has started is so impressive and we've still not seen Filipe Luis, who is a top player. And the money they've spent is not too bad when you compare it to United.

JAMIE REDKNAPP: Chelsea did their business early and got £50million for David Luiz. Further down the table, Aston Villa did well to keep Ron Vlaar. And I really want Tom Cleverley to do well. He's been a scapegoat for too long.

MARTIN KEOWN: It's a full house. Chelsea won it the day they sold David Luiz for £50m. And then they got £28m for Romelu Lukaku. Unbelievable business. Financial fair play rules have made them become better negotiators.

Is Danny Welbeck good business for Arsenal?

KEOWN: It is good business. United are becoming a team of galacticos and he doesn’t fit into that. I’m not sure United have ever been convinced about him. It will be exciting for him to work with Arsene Wenger. He improves young players and has a superb record with top strikers: Klinsmann, Weah, Bergkamp, Henry. 

Welbeck is not clinical in front of goal but he’ll practise that. I remember Emmanuel Adebayor rarely hitting the target when he first joined Arsenal but Wenger had him practising and the improvement was phenomental. He’s the same price as Mario Balotelli but Welbeck will be here for the long term, Balotelli won’t. My only worry is that he could be in mourning about leaving such a great club. He needs to realise he has joined another and can finally take centre stage.

CARRAGHER: I can see the positives of his move from both sides. His goalscoring record isn’t great so I can see why United have moved him on. A lot of people at United will be loath to see a local lad go. And he has real pace, which United don’t have much of. He’s a good fit for Arsenal but he’ll play a similar role: sometimes he’ll be out wide, sometimes through the middle and sometimes on the bench. Is he really going to be their No 1 striker?

REDKNAPP: I like him and always hear good things about his attitude and personality. He’s a good athlete but doesn’t score enough goals and doesn’t get in the right positions enough. I’m pleased for Arsenal fans that they signed someone. Welbeck is going there with a real point to prove.

Outside the heavyweights, who got the best deal?

REDKNAPP: Hull signed match- winners in Gaston Ramirez and Hatem Ben Arfa. And I won’t apologise for saying it but Sandro is an excellent signing — he’s a monster, exactly what QPR needed. He’s got a tremendous attitude and work ethic and is an infectious character who will rub off on everyone.

KEOWN: Hull landing Ben Arfa. He was never a bad player, he just fell out with Alan Pardew. He has so much ability.

CARRAGHER: I agree on Sandro. He’s a big strong player, who impressed me for Tottenham. He has a physical presence and QPR needed Premier League experience. They just have to keep him fit.

One signing you wish had happened...

CARRAGHER: I’d have loved to have seen Xabi Alonso come back to the Premier League instead of moving to Bayern Munich. He’s such a good passer of the ball.

KEOWN: Toni Kroos. I don’t know why Van Gaal didn’t want him. Instead he went to Real Madrid. He passes the ball so cleanly.

REDKNAPP: I agree with Jamie on Alonso and would have also liked to have seen Arsenal sign Falcao. They are so close to being title contenders.