Summers's musicality impressed Sting, who was becoming frustrated with Padovani's rudimentary abilities and the limitations they imposed on The Police's potential. Shortly after the Strontium 90 gig, Sting approached Summers to join the band. He agreed, on the condition the band remain a trio, with him replacing Padovani. Restrained by loyalty, Copeland and Sting resisted the idea, and The Police carried on as a four-piece version. However, they only performed live twice: on 25 July 1977 at the Music Machine in London and on 5 August at the Mont de Marsan Punk Festival. Shortly after these two gigs (and an aborted recording session with ex-Velvet Underground member John Cale as producer on 10 August), Summers delivered an ultimatum to the band and Padovani was dismissed. The effect of Summers's arrival was instant: Copeland said: "One by one, Sting's songs had started coming in, and when Andy joined, it opened up new numbers of Sting's we could do, so the material started to get a lot more interesting and Sting started to take a lot more interest in the group."