Arsenal are stepping up their bid to land Sporting CP winger Gelson Martins.
According to Corriere Dello Sport, Arsenal and Lazio have emerged as front-runners for the signature of Gelson.
The 23-year-old is in the process of trying to annul his Sporting contract but possesses a £52m buyout clause at the Portuguese club.
However, the Gunners can tempt the winger to England by offering superior terms.