It's probably the last thing the Once-ler was expecting to happen, and he's not ready for it at all.

He's lanky and too thin, so he's tugged forward with ease. Before he can even react, Phil has him by the collar of his shirt, but from there the Once-ler fights to tug himself free. Unfortunately is head still catches the edge of the desk when Phil slams him down and everything feels weirdly light for a second just before he hits the carpet with a heavy thud.

For a minute or two he just stays there with his eyes shut, listening to the ringing in his ears. That hurt, but eventually it sinks in that Phil is still there and Phil definitely just tried to slam his head into a desk, and that's enough to make him sit up very suddenly and stagger backwards. He's very wobbly and his head...he reaches up to touch it (and misses in the first attempt and has to try again) and when he pulls back his hand there's blood on the tips of his gloved fingers.

He's gone from wanting to help Philip to being terrified for his own life.

"Phil? Ph-Phil, don't-! Come on, whatever you're...whatever's in your head, that's not real! Phil!"

As he tries to talk his way out of this, he inches back, trying to get closer and closer to the door.