"Mido was obviously key to us getting back in the game and he took the free-kick superbly," Southgate said.
"But different games require different players and I thought Julio Arca was excellent when he came on.
"He got hold of the ball for us, made us play a bit more and allowed us to use the width of the pitch a bit more. It was pleasing for me to see that.
"That's football and the nature of being part of a team and I thought the defence did very well when they were under put under pressure."
Southgate added: "It is nice to have people coming back to fitness to give me a strong bench. Justin Hoyte coming back is good, he is able to give us something going forward as well as at the back.
"Although he didn't play in his natural position I felt he would give us something going forward in the second half.
"David Wheater had a solid first half but he's not quite as comfortable on the ball going forward so I thought Justin would give us that bit more width and he did well for us.
"I told the lads at half-time that we need to be sharper and get the ball out wide more and obviously made a substitution for that reason."