In incredible scenes at AAMI Park on Friday night, Heart played for almost an hour with just 10 men after Orlando Engelaar's 33rd-minute dismissal for a crude tackle on Hagi Gligor.
Yet despite going a goal down just minutes later as Corey Gameiro found the back of the net, Heart found some true grit as they came from behind to defeat the Sky Blues through goals to Jonatan Germano and an 89th-minute special from David Williams.
Williams' goal was one out of the box as he took possession in his own half and accelerated forward, dodging challenges from Matt Jurman and Richie Garcia before firing home a spectacular goal.
The 25-year-old's effort sparked euphoric scenes amongst the 7674 crowd at AAMI Park while on the pitch every Heart player threw themselves into an almighty bear hug on the turf in sheer relief as the side delivered just their second win this season.
"It was a really good goal, fantastic," declared van 't Schip.
"For him I think it's very important, being injured the last week, coming in, coming out and every player needs some times a good moment.
"For David it was a fantastic moment, he did everything on his own and showed in that one moment that he has a lot of quality.
"I'm only here for a few weeks now and David has to bring more," van 't Schip added with a word of warning.
"Like all the other players they have to believe more in themselves. (But) the confidence is growing."
Van 't Schip's words come as the entire Heart squad find themselves on notice, their careers on the line following Manchester City's takeover of the club last week.
Already City football administrator Brian Marwood has been observing training sessions over the last week, while Marwood attended Friday night's game alongside Football Federation Australia chief executive David Gallop.
However, being part of the Manchester City stable appears to have inspired Heart as they were the better side for much of this encounter while Sydney FC failed to bring the intensity they displayed in last week's 5-0 mauling of Melbourne Victory.
"I think if you come behind 1-0, 10 men, you know it's going to be a hard game," van 't Schip said.
"But I think from the start we played well, we created not maybe that many chances but we were playing good football.
"Then when Orlando got sent off, of course it changes but still then we kept on playing forward.
"Just before half-time, the breakout from Jason Hoffman with (Iain) Ramsey, I couldn't see but it was a dangerous moment and could have been maybe a penalty.
"But those moments gave the boys a lot of confidence and in the half-time I told them that this game wasn't over and playing against 10 men, if you do it well, you're organised, it's not easy."
