MICHAEL Jamison may well have been the one player Carlton could least afford to lose in Sunday's game against West Coast.

Chris Judd and Marc Murphy might be the more high-profile players around Visy Park these days but against a tall and versatile West Coast forward line, Carlton hearts sunk when Jamison had to be subbed off with a knee injury before half-time.

Few felt the loss as acutely as fellow defender Bret Thornton.

"He's one of our most important players so when we lose him early on, it was a huge loss and we probably struggled. They were already tall as it was, so to lose him was a bad result," Thornton said after the game.

Thornton stood up to the challenge, rotating between some of the key Eagle forwards while also gathering 26 possessions himself.

But he admits it was hard work to try to cover Jack Darling, Quinten Lynch and Josh Kennedy along with Nic Naitanui and Dean Cox when they rested from ruck duties.

"It's pretty effective and pretty hard to match up on. There are four genuine talls down there at some stages so they are going to cause some headaches and go pretty deep in September," he said.

"A few blokes had to play taller so that probably threw us out a bit. Losing 'Hendo' from the forward line and putting him down back wasn't great for us but we've got to be better than that and got to put the ball to ground."

Thornton said he saw worrying indicators from early in the game that the Blues weren't completely switched on.

"West Coast were always going to be a great challenge today. The warning signs were there from early on. We were just off our game and we've got to get back on the winners' list as soon as we can," he said.

"Richmond will be a good challenge on the MCG next week so hopefully we can bounce back."

The Tigers will be no easybeats for the Blues, who may have to face star forward Jack Riewoldt without Jamison, who will undergo scans on his knee on Monday.

If he doesn't recover in time, Thornton may yet again have to fill the breach.

"Hopefully 'Jamo' will get up. Riewoldt is one of, if not the best forwards in the comp so it is going to be a huge challenge for whoever plays on him."