Something changed with Grabbing?

I was a 13.5t deino and another fg deino was able to grab me today in the water. They couldn't hold me for more than a second or two, but that was enough to drop my o2 by about 1/8th or so, they just kept grabbing me over and over until i drowned. I don't understand how that's possible. Also, last week i was a fg steg and a deino grabbed me on land and it seemed to hold me in place, i couldn't get away or swing my tail.

Did something change with the grab mechanic?