Jay Stansfield has scored in both his appearances this season
Substitute Jay Stansfield scored a late winner to give Birmingham City a deserved victory over Sheffield United in the Carabao Cup.
The hosts were gifted an opener inside five minutes when debutant Dovydas Sasnauskas sold keeper Adam Davies short with a backpass and Demarai Gray nipped in to tee up Kyogo Furuhashi to score.
The Japanese then missed two gilt-edged chances to add to their lead and they were punished in breathtaking fashion when Gus Hamer scored from just over the halfway line with a superb strike.
Blues were not to be denied, though, as Stansfield turned adroitly on the edge of the area and his low shot took a deflection on its way past Davies.
They will now host League One Port Vale in the second round.
Birmingham manager Chris Davies made six changes from the side that conceded a stoppage-time equaliser to Ipswich in the opening Championship game of the season, while Blades boss Ruben Selles made 10 alterations from their shock 4-1 defeat by Bristol City.
As on Saturday, the South Yorkshire side were a goal down within five minutes.
Teenager Sasnauskas' error was punished by Kyogo. But after his opener, the former Celtic player then miscued when clean in on goal and scuffed another shot wide when well placed as Birmingham dominated.
The visitors almost equalised against the run of play when Tom Cannon's deflected shot hit the outside of the post.
There was some controversy when Ethan Laird was denied a second goal for the home side when he powered in a header from a corner after referee Gavin Ward had blown for an infringement in the area after the set-piece had been taken.
Blues' sense of injustice deepened when Hamer scored a stunning leveller after the ball had appeared to hit Ward before breaking to the playmaker.
Stansfield, on for Kyogo, had the final say though, and Birmingham will look to continue their positive start to the season when they visit Blackburn on Saturday.
Meanwhile, United will hope to put an end to their losing start when they play Swansea on the same day.
What they said
Davies: 'We didn't let them settle'
Birmingham boss Chris Davies told BBC Radio WM:
"I thought again we were excellent. We carried on from Ipswich, we were very aggressive, we didn't let them settle. I thought we were the better team.
"We just could have scored a few more goals to put the game to bed. Even defensively, I thought we were super. So, a lot of positives.
On Sheffield United's goal: "The goal that they scored, I was really upset at that because we did not have possession back after it hit the referee.
"We saw the ultimate consequence today when you get a player of that quality, who can shoot from there, it shows you how important it is to get that right and I think the rule is, it's a disallowed goal."
Sellés: 'We make some basic mistakes'
Sheffield United boss Ruben Selles told BBC Radio Sheffield:
"We made some basic mistakes at the start of the game - that made the game difficult for us.
"After half time we became more competitive and then with one moment from Gustavo we equalise.
"For some of the players it's a first experience in a stadium like that, there were some mistakes but it's part of the journey."
