After inheriting a team which had won only twice in 24 matches, Redknapp scrapped the three defenders and wing-backs formation favoured by his predecessor Gianfranco Zola, who quit this week, introducing a rigid back four with Lukas Jutkiewicz the focal point of the attack as a lone striker.
For long periods it worked and the improvement in the team's performance was there for all to see, as a largely dour encounter looked headed for a goalless stalemate
However, substitute Gabby Agbonlahor's second-half goal settled the contest
A 1-0 loss at Villa Park was not the start Redknapp hoped for after this week agreeing to oversee Birmingham's remaining three games following the departure of Zola
T he Blues stay one place and two points above the relegation zone and Redknapp has a home fixture against Huddersfield on Saturday before a potentially crucial final-day trip to Bristol City to fulfil his remit of keeping Birmingham up
"I take a lot of encouragement from that," said the 70-year-old
"The attitude has been terrific all week, everything we asked them to do in training they have done today
Would they be able to carry that on to the pitch with them? I thought they did
They worked their socks off, I can't ask for more from them
They gave absolutely everything
"I feel a lot more confident than when I walked in on Monday
I looked at the record - two wins in 24 - and I thought, 'my God we need a miracle'
Don't get me wrong I know it will still be tough but I was really pleased with them today.
"Our keeper hasn't had a shot to save, I don't think he touched the ball did he? How we've lost that, I do not know
"They created nothing
I thought if anyone was going to nick it then it was going to be us
I could never see us getting beat
A point would have been handy so it was a blow not to get anything out of the game.
"Huddersfield next week is a massive game and we have to make sure St Andrew's is rocking
I hope the fans are pleased with what they saw today
The result isn't what we wanted but they can't fault the effort
I can't fault the effort."
Villa boss Steve Bruce acknowledged the work Redknapp had done in a short space of time before going on to praise match-winner Agbonlahor
"I have to say, Harry managed to sprinkle his magic in five days because the difference between them today and where they were last week was unbelievable
They showed they care and it was a really tough game," said Bruce.
So often the scourge of Birmingham, Agbonlahor's introduction from the bench just before the hour immediately brought life to the game
Making his return from a three-month lay-off with a hamstring injury, the 30-year-old was immediately in the thick of the action, getting involved in a scuffle with Ryan Shotton before being booked and showing his fists to the Blues fans.
He then made the telling contribution in the 68th minute, just nine minutes after entering the action, when he turned the ball home following a scramble inside the penalty area for his first goal since February 2016.
Bruce said: "He tried everything he possibly could to be fit and I'm delighted for him, because when he was close (to returning) last time he did his hamstring and was back in the treatment room
All the work he'd done was undone
"He showed what it means to him, he showed passion
As soon as he came on he's making a challenge, he's tearing after somebody
He lifted the whole stadium
He changed the whole atmosphere inside the stadium as soon as he walked on to the pitch
"Fair play to him, he's won us the match
We've scored off a set-piece - a sloppy one at that
But we'll take it."
Source : PA