PORT ADELAIDE coach Mark Williams has praised the mental strength of his players following their stirring come-from-behind victory over Essendon.

Following the second-term loss of Warren Tredrea, the only sour note on the day, Port was under siege in the third quarter and trailed by two goals heading into the final term before summoning a stunning surge that secured the premiership points.  

"It's a great achievement for our club and our players to be able to draw from adverse conditions and to be able to keep coming and get over the line," Williams said of his club's fourth win of the season after having trailed at three-quarter time.

"We've got a lot of confidence and a lot of real belief over the last few weeks. It's happened a lot of times this year so it can't be a fluke; it's really to do with their mindset. It was a great effort and all credit to the players.

"We talked about what we had to do at three-quarter time, but it wasn't about us talking, it was about us delivering and they got out there and delivered.

"It's a wonderful trait to have and it's fantastic to be the coach of a side [like that]. There was no individual person who did anything great in the last quarter; there were 22 or 21 without Tredrea."

Tredrea fell awkwardly in a marking contest and has damaged ligaments that should see him miss at least a month of football, Williams said.  

"There's a ligament [between the foot and the leg] there you kind of stretch - it’s like doing an ankle but it's a little bit worse than an ankle strain," he said.

Daniel Motlop, Brett Ebert and Justin Westhoff all stepped up with three goals each in Tredrea's absence, with the trio's ability to nail some difficult shots drawing the praise of the coach.

Danyle Pearce also earned a mention for his outstanding performance in his 100th AFL game.

"It's certainly one to cherish and remember - he's been outstanding for us," he said.  

"He's a wonderful finisher. We made a 100-game tape for him and he's got some of the best highlights you'll every see."

With five wins on the board from seven starts, the Power has exceeded expectations outside the club's walls at this point in the season, but Williams said his side's 10th place finish in 2009 would serve as a strong deterrent against complacency.

"We felt like we were a chance to make the finals [pre-season]," he said.

"We're still on course for that, but it's a really long year - we were 4-2 last year."