The reigning champions triumphed 2-1 at Dens Park with Yang and Kelechi Iheanacho netting either side of a Simon Murray equaliser from the penalty spot.
It was a crucial three points for the side as they are now just three points behind leaders Hearts and two shy of the Light Blues.
Former captain Scott Brown was impressed with the team’s effort, with special praise reserved for winger Yang.
He displayed immense workrate off the ball, according to Brown.
Brown said: “Yang, he has put a power of work in, off the ball as well.
“He’s underestimated.
“I know we talk about Daizen Maeda all the time but Yang does put in so much workrate for the team off the ball.
“On the ball people always expect him to do things but people forget about that side of the game.”
It was the winger who put Celts ahead with a deft touch as Benjamin Nygren attempted to nick it off his toes on the goal line.
However, it was Dens striker Murray who restored parity for the hosts, capitalising on a handball from Colby Donovan to convert from the spot.
With just minutes left on the clock, Iheanacho, a substitute for Celtic, clinched the game with a match-winning goal.
This victory puts Celtic just three points adrift of Hearts and two behind Rangers, with the title race heating up.
Before the match, Martin O’Neill had acknowledged the significance of winning and rallied his squad for full commitment.