Southampton and Middlesbrough will face each other in the Championship play-offs
The English Football League (EFL) has launched an investigation into an alleged case of spying by Southampton on Middlesbrough before they meet in the Championship play-offs.
The first leg of their semi-final takes place at the Riverside Stadium on Saturday, with the return at St Mary's on Tuesday.
BBC Sport has learned Saints' performance analyst was allegedly caught recording Boro training and taking pictures of tactics late on Thursday morning.
The staff member was caught, told to delete the footage and leave the area, but the Teesside club were furious and later contacted the EFL.
