Cardiff City substitutes Eoin Doyle and Matthew Kennedy "changed the game" in their 2-0 win against Birmingham, according to Bluebirds assistant manager Scott Young.
Kennedy set up Doyle to give Cardiff the lead with his first goal for the club.
Young praised the deadline-day signings for sparking a first home victory for the Bluebirds since January.
"I thought the two subs changed the game for us," Young said.
Since joining from Chesterfield for a fee of around £1m, Doyle had played eight games for Cardiff without scoring.
But he made a telling contribution from the bench against Birmingham, coming on to score the opener and then win the penalty which Peter Whittingham converted for Cardiff's second goal.
"Doyley's played a few games and been very unfortunate not to get off the mark in those games," Young said.
"Things didn't fall for him, we've taken him out [of the team], he's come back and had a real impact as a substitute and got the goal he deserved."
Before beating Birmingham, Cardiff had not won at home since they marked their return to their traditional blue kit with a 1-0 triumph against Fulham on 10 January.
Impressive performances on the road - including three wins from their last three away matches - compensated for a run of seven games without victory at Cardiff City Stadium.
Young was relieved to finally end that sequence with a comfortable win against Birmingham.
"A few times at home since the start of the New Year we've been in good positions and we haven't got over the line," he added.
"So it's pleasing. The clean sheet was a big one and it's pleasing to get the three points."