Joe Rothwell made his Southampton debut in Saturday’s 3-1 win over Swanseas City as he came on for Stuart Armstrong in the 76th minute. Rothwell was a surprise signing as midfield was not an area that Southampton were expected to target this month. Having joined the club on loan from Bournemouth on Monday it was straight into the squad on Saturday for Rothwell. Fellow loanee Flynn Downes spoke of how he was impressed with his first look at Rothwell after training on Tuesday, but the 29-year-old struggled to make an impact on his debut having replaced Southampton’s best player on the day. The e…