Kostas Manolas
Manolas is seen as a direct replacement for VermaelenReuters

Olympiakos defender Kostas Manolas is reportedly on the verge of sealing an £8 million move to Arsenal, after successfully undergoing a medical at the Emirates.

The north London outfit has been keeping a close eye on the Greek international for some time, and has now reportedly identifed Manolas as a direct replacement for Thomas Vermaelen, who recently completed a £15m switch to Barcelona.

It was earlier believed that Seria A champions Juventus were leading the race to land the the 23-year-old, with Christian Karembeu, the Strategic Advisor of Olympiacos, confirming that the club received a "sound offer" from the Italians.

"Juventus are interested and have made a sound offer. We are in contact with Juve chief Giuseppe Marotta; we will see in the next few days if any meetings come from this," Karembeu had earlier told Goal.

However, with Karembeu recently revealing that they have also received some "interesting proposals" from England, and that Manolas would not be allowed to leave for "less than €10m", Juventus were understood to have pulled out of the race, making Arsenal the favourites.

And now, the Independent reports that the Greek defender is on the verge of sealing an £8 million switch to Arsenal, after successfully undergoing a medical at the Emirates.

Meanwhile, Arsenal boss Arsene Wenger feels that his men are "short of preparation", ahead of their first leg Champions League qualifying clash against Besiktas.

While Besiktas played their last competitive fixture (Champions League, third qualifying round) on the 6 August, Arsenal have already been involved in two competitive fixtures - against Manchester City (Community Shield) and Crystal Palace (Premier League) - in the last 10 days.

And, right after their trip to Turkey, the Gunners face Everton at the Goodison park on Saturday. Wenger feels that his side have a big challenge this week.

"This is a big test. We had a short preparation and we know that in one week we have three big games: Besiktas home and away and Everton in between," Wenger told Arsenal's official website.

The Frenchman also insists that the Gunners will not underestimate the Turkish side, who will be full of confidence, following their victory over Feyenoord in the third qualifying round.

"Every challenge is different and beating a Turkish team away from home is very difficult but we want to perform at our best. Besiktas are on the back of a good result against Feyenoord but we're on our toes and want to produce a good result."