"There is no going back now, Rishi Durvasa fully awakens the Rudra part in him."
Sukracharya standing right in front of the beast was the one one to saw the changes happening and become uneasy.
It's no joke to stand in front of Rudra, Even if it's just time part of one but it's still Rudra literally means the most fierce one, The one who is said to be like a beast on a hunt.
He knows that there is no way he can stop Rudra as his own without external help and that help has to be equal or even higher than the part of Rudra, Durvasa using.
And thankfully Sukracharya has it, he has the power not only to defend against Rudra but also with it he can even force him back but there is just one small problem.
Just like Durvasa he can't control that power, or to say no one extract one can control that power, Once he awaken that power he will able to put a fight against Rudra but what after that?