The 25-year-old was the recipient of individual awards for his stellar displays in Chelsea's Premier League and Capital One Cup successes last season, but he has struggled for form this time around, including in last Tuesday's Champions League loss at Paris St Germain.
Hazard, who sent a text message apology to Jose Mourinho after the Portuguese was sacked in December, showed signs of his best against a much-changed City and scored Chelsea's fourth in the 5-1 win which set up a quarter-final with Everton
He also set up two goals.
It was just Hazard's second goal of the season
Both have come in the FA Cup after his penalty in the fourth round at MK Dons on his first start following a groin injury in early January.
"Eden Hazard came back very strong
That's what I like very much," Hiddink told Chelsea TV.
"He has had setbacks in recent period caused by injuries and it's not easy to come back.
"He trained well
Bit by bit he got more minutes in the games and it's rewarded now by his assists and goal
That's good.
"Everyone was focusing on him
Of course we protect him, but we also ask him what he can do - and he did (show what he can do)."
Hazard revealed on the eve of the PSG contest that it would be difficult to turn down a move to the Ligue 1 champions, while also reiterating his contract with Chelsea runs until 2020.
And Hiddink was forced to deny Hazard was agitating for a move away from Stamford Bridge.
The Belgian's place in Chelsea's starting XI against City might have been in doubt, but Hiddink named an unchanged line-up and Hazard justified his faith.
City made the promised changes, but Hiddink resisted amending his line-up, with his players keen to play.
"It's hard to say, 'hey, I want to rest you', then I get an eyebrow raised, 'I don't want to be rested'
And that's a very good sign," Hiddink added.
Defender Tosin Adarabioyo was one of the City players to benefit from Manuel Pellegrini's decision to make nine changes and prioritise Wednesday's Champions League last-16 first leg at Dynamo Kiev.
Adarabioyo hopes the fact six teenagers played for City will show there is a pathway to the first team.
The 18-year-old, one of five full debutants, said on City TV: "I think this will inspire a lot of the youngsters to work really hard
You can see the results of us five starting, to try to get into the first team.
"It was a very good experience for all of us to play against the Premier League champions
We all learnt something.
"They're a lot older than us
We had a lot of youth players in the team
Experience comes down to it (the result)."
Source : PA
Source: PA