Southampton look set to make their third signing of the summer as they prepare for their return to the Premier League. Taylor Harwood-Bellis was the first arrival, with the 22-year-old’s Manchester City loan made permanent for £20 million following promotion being confirmed. On Friday, Southampton announced an emotional return to the club at which it all started for veteran Adam Lallana following the expiration of his Brighton contract. Manager Russell Martin knows he has work to do this summer to get his squad ready for what will be a difficult season in the Premier League in which survival i…