Brendan Rodgers praises hat-trick hero James Forrest after Cup win

In a whirlwind start to the lunchtime encounter, the 26-year-old notched twice in the opening 10 minutes before Jags striker Kris Doolan reduced the hosts' lead.

Forrest's third in the 53rd minute was his 16th goal of the season before Jags substitute Conor Sammon, on for Doolan, fired in a late second for the spirited visitors, although it was not enough to prevent the holders going into Sunday's quarter-final draw.

Rodgers, who will now prepare Celtic to play against Russian side Zenit St Petersburg in the first leg of their Europa League clash on Thursday at Celtic Park, said of Scotland international Forrest: 'He was brilliant, absolutely brilliant.

'His game has come on this year again, into being a really effective player because he has got that ability.

'He is technically very good, one of the best receivers of the ball I have every worked with, in how he takes the ball on the side of the field or in the middle.

'He has a wonderful touch and how he can move it with his second touch and now he is adding goals to his game.

'He has that hunger to score goals and all three of them were outstanding today.

'He was the class player on the pitch and thoroughly deserves the match ball.'

The Northern Irishman admits his side will have to improve if they are to retain the trophy.

He said: 'We got through which was important. Certainly if we want to win the cup again we will need to defend better and play better from behind.

'We got into a great lead at 2-0 up but made a poor mistake which gave them a bit of oxygen and impetus.

'We started the second-half well in the second-half and got the goal.

'Some of the combinations were good but the build-up play was too loose from behind and they get their goal again.

'Kieran Tierney does a brilliant piece of defending at the back post when they could have made it 3-3 which would have been a really poor scoreline for us.'

After scoring his first hat-trick for the club, Forrest said: I am absolutely delighted and getting into the next round as well, it was a good day all round.

'I have been on two goals before and had a couple of chances but not managed to get a hat-trick so I was delighted to get it.''

Unsurprisingly Thistle boss Alan Archibald bemoaned his side's slow start to the match.

He said: 'There are positives to take from it, if you get the first 15 minutes out of my head.

'It was a terrible first 15 minutes start to the game.

'We can't start any game like that, especially here, which was a big disappointment but the guys showed great character to come back from that.'