Manchester United and Manchester City will battle this summer for Porto defender Eliaquim Mangala.The Sun says United pose the biggest threat to Manuel Pellegrini's City plans, having sent scouts to check on Mangala over the weekend.

Valued at £38million by Porto, the 23-year-old would become United's record signing, edging January acquisition Juan Mata.

Boss David Moyes is expected to complete a squad overhaul this summer, with chief executive Ed Woodward admitting the club could make more than three major signings.