Arsenal manager Arsene Wenger admits the pressure is on for him sign the next Lionel Messi rather than another promising player in the January transfer window.

The Gunners have been linked with a £10million bid for Atletico Madrid striker Adrian Lopez, while Crystal Palace's 21-year-old England international Wilfried Zaha and Schalke midfielder Lewis Holtby are others allegedly on Wenger's radar.

However, as he looks to bring in players who can make an instant impact, Wenger knows Arsenal fans patience is wearing thin when it comes to keeping faith in potential to deliver.

"It is very difficult because the level of expectation is very high - people want to see Lionel Messi come in, they don't want to see a promising guy," said Wenger, who takes his side to Swansea in the FA Cup third-round on Sunday.

"First of all the name gives hope. When a guy has no name people are already sceptical, so it's much more difficult for us."

"The emerging countries now to produce players look to be Germany and Spain, who have many good young players" - Arsene Wenger

Swansea look to have picked up a real bargain in Michu, signed by manager Michael Laudrup for just £2million from Rayo Vallecano, and the Spanish striker scored both goals in the 2-0 win at Arsenal on December 1.

Wenger admitted the 26-year-old had not been high on the watchlist of the Arsenal scouting network, which is now under more scrutiny than ever to unearth talent who can hit the ground running.

"Sometimes when you are on a big club your scouts are a bit more cautious because they think 'oh, it is Arsenal it has to be a top four player', so naturally they are looking less at players who play at smaller clubs," Wenger continued.

"You are always scared that he is a player who does not do well, the scouts are looked at as responsible.

"The competition is higher on scouting front, that is for sure.

"The country where we were really, really competitive was France, but now they produce less players than they did 10 or 15 years ago at the top, top level.

"The emerging countries now to produce players look to be Germany and Spain, who have many good young players."

Arsenal had been strongly linked with a move for Senegal international Demba Ba, who is now in talks with Chelsea after they met the £7m release clause stipulated in the deal he signed with Newcastle during the summer of 2011.

Wenger, however, maintained he decided against looking at the transfer, having already signed Olivier Giroud from Montpellier in a £13million deal during June.

"I like Demba Ba personally, he is a similar type to Giroud who we just bought. It was one or the other one," Wenger said.

"They are similar positions and similar types of players."

Ba had failed a medical with Stoke before eventually joining West Ham in January 2011.

Wenger, though, would not have been put off a potential deal because of the reported problems.

"I'm a bit cautious about the noises on that front because I've heard different vibes coming out," the Arsenal boss said.

"Someone told me that what he has is manageable that it can be prevented and have no problem.

"Some people say he didn't manage to pass the medical at Stoke, but the last things I heard it's quite positive for him.

"I am sure Chelsea will have a check on that and if they sign him it is because the problem is not as big as people say."

Arsenal have no fresh injury problems ahead of the trip to Swansea, where Theo Walcott could again be deployed in his favoured central role.

Wenger remains hopeful a deal for the out-of-contract England forward can be secured sooner rather than later.

He said: "It is a positive message for us to keep Theo, of course. Will it have an effect on the morale of the team? Yes, I am convinced it will have a positive effect if we manage to sign him."