Frank Lampard believes Alexis Sanchez signing will give Manchester United an extra dimension

The Red Devils completed the signing of Alexis Sanchez on 22 January. The Chilean international arrived at Old Trafford from Arsenal and Henrikh Mkhitaryan moved in the opposite direction as part of the deal. The Chilean made his United debut in a remarkable fashion, picking up two assists against Yeovil Town in the fourth round of the FA Cup, a competition he has won twice with Arsenal.

Jose Mourinho substituted the Chilean with around 19 minutes remaining and Sánchez's patience wearing thin with some of the treatment meted out. The forward, arguably the highest-paid player in the Premier League, was subject to a couple of ruthless challenges, which Mourinho said could have been a red card for the defender in question, Nathan Smith.

Lampard is optimistic of the impact Sanchez will have at United, stating that he can bring a spark back to the club akin to the arrival of Eric Cantona, who was a cult figure at Old Trafford. His arrival will challenge all the teams in the top six to match United's ambition.

"The signing of Alexis Sanchez will give Manchester United an extra dimension, Lampard told the Sun. "He can bring the kind of spark to the club which Eric Cantona provided all those years ago. You can talk about how much he's costing United but, in terms of the player, Sanchez is world class.

"I love watching him play, his balance, his turn, his skill and his competitive edge. United have some very good players and they're a solid team. But Sanchez will add an extra edge. The Sanchez deal asks questions of all the other top six teams and challenges them to match it."

Lampard also had a word of caution for Chelsea to start strengthening their squad as they are being left behind by the transfer activity of clubs around them. The Blues have not brought in quality players in January while there are question marks over the future of Thibaut Courtois and Eden Hazard, who are stalling on signing a new deal.

"Chelsea have the power to match them but it's something they haven't particularly done in recent years. Don't get me wrong, they've spent good money. It's not as if they've suddenly stopped buying players. But other clubs are spending more and they have to be careful not to get left behind.

"Eden Hazard is the centre-piece of the club and has been the catalyst for their very good performances over the last 18 months. Players will move on but hopefully not Hazard. Chelsea have to try to keep him and build the team around him."