Kept possession well, but didn't really create any great opportunities. We were never really going to trouble Southampton through the middle, with Wanyama and Schneiderlin sitting in front of the back four, so we needed to get it wide more often that we did. In the first half, we created a few problems for them with Valencia down the right, who I felt had a good game today. In the second half - however, we very rarely got into wide areas. The few times we did, we created chances, and Mata's three opportunities we created after Southampton scored, come from getting it wide and getting it into the box.
Having said that, with Rooney and Mata, we were never going to penetrate through a compact Southampton. They kept it well enough, but we lacked someone who could take on players through the middle, thus creating more space for others or themselves. Like Carragher said in his post analysis, Di Maria was that player, and should have swapped positions with Rooney, instead of Herrera replacing Di Maria.
Away from that, though, I think we defended well enough. Felt Smalling was dominant, and we were pretty good playing out from the back. Unfortunately, the players ahead of them didn't create much.