Atletico Madrid's Diego Costa lines up an overhead kick next to Chelsea's David Luiz during their Champion's League semi-final first leg soccer match at Vicente Calderon stadium in Madrid, April 22, 2014.
Atletico Madrid's Diego Costa lines up an overhead kick next to Chelsea's David Luiz during their Champion's League semi-final first leg soccer match at Vicente Calderon stadium in Madrid, April 22, 2014.Reuters

Arsenal have joined Chelsea in the race for Diego Costa and are willing to match Atletico Madrid's valuation of £31m for the player, according to the Mirror.

The Spain international has been among the most prolific scorers in Europe this season and will be a major boost for the Gunners, who are looking for a world-class striker to supplement their title challenge next season.

Olivier Giroud, in spite of scoring 20 goals in the current campaign, has been vastly inconsistent and has missed more than he has scored, something which the Gunners are sure to look at in the summer.

The absence of Theo Walcott and Aaron Ramsey did not help their cause in the second half but a player of Costa's calibre in the box could have narrowed the seven-point gap between Arsenal and the Premier League title contenders.

Wenger revealed that he needs an attacking player in the summer who can play alongside Giroud to increase their options up top and Costa, who has scored 27 goals and assisted three this season, fits the bill.

"There is perhaps room for an attacking player who can play in a different position to Giroud. Someone who can play with him as well. But I do not know yet who will be on the market," Wenger said.

However, Wenger will face tough competition from his arch nemesis Jose Mourinho, who is also looking to replenish his strike force with a forward and Costa is reportedly top of his list.

Both clubs are likely to splash the cash in the summer, with Wenger stating that he will move in for two or three players who can improve his side rather than shop for quantity.

The Gunners are likely to be in the market for an attacking player, a holding midfielder and a right-back should Bacary Sagna leave the club.