Celtic striker Anthony Stokes admits he needs to keep producing quality performances on the pitch to keep his place in the Parkhead club's starting line-up.

The Hoops hitman has started the season in fine form, netting three goals in the opening four league games including a late winner in Celtic's last run-out against Dundee United.

However, Finnish striker Teemu Pukki has since arrived at the Glasgow giants on transfer deadline day from Schalke 04 to increase the attacking options at Celtic Park and Stokes knows that he must maintain high standards to preserve his place in Lennon's starting 11, starting with this Saturday's trip to Tynecastle to take on Hearts.

"Normally I have done alright at the start of the season," the Irish international said.

"In the last couple of years I have done well in the first couple of games and I just need to try and maintain it now.

"We have some other players coming in and have competition up front, so everyone needs to be on top form to keep their place in the side.

"At a club like this there is always that bit of pressure as there are always four or five players competing, especially up front, for two places. Since I have come here, it's been the same.

"Competition is always there and you just forget about it and play your own game.

"New lads have come into the squad and hopefully they can contribute.

"We've started well, we have qualified for the Champions League and we are doing well at home in the Premiership so we want to continue that and improve."

Celtic will be without Mikael Lustig for the trip to Tynecastle after he picked up an injury when on international duty with Sweden.

It's a huge week for the Glasgow giants as they face Hearts before travelling to Italy to open their Champions League campaign against Seria A cracks AC Milan.

However, even with a crucial European clash on the horizon Hearts manager Gary Locke doesn't expect Celtic's concentration levels to drop.

"I don't think they will have their guard down in any way," said Locke, whose side sit bottom of the Premiership as they try to eat into a 15-point deduction handed down for going into administration.

"We're playing against the champions who have a team full of international stars. It is a great test for our young players.

"There is more pressure on their players but that's the thing about playing for a club the size of Celtic, there are demands on them to win every week.

"I don't know what Neil is thinking with regards to his plans for their Champions League game. He might make a couple of changes, he might play his full-strength side and that's certainly what I think will happen.

"He will admit that Tynecastle is a tough place to come to and I'm sure he will come here wanting to take three points, but we feel we can cause them one or two problems."

Elsewhere on Saturday, league leaders Inverness Caledonian Thistle make the long trip to take on Kilmarnock at Rugby Park, while Partick Thistle will try and continue their good start to the season as they host Aberdeen at Firhill.

St Johnstone welcome Hibernian to McDiarmid Park as Motherwell travel to St Mirren. And, on Sunday, Ross County take on Dundee United at Victoria Park.

Fixtures (1400 GMT unless stated)

Saturday

Hearts v Celtic (1130 GMT), Kilmarnock v Inverness CT, Partick Thistle v Aberdeen, St Johnstone v Hibernian, St Mirren v Motherwell

Sunday

Ross County v Dundee Utd (1145 GMT)

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