Jim Mallinder’s men head to Kingston Park on the back of nine successive league wins, which have taken them to the Aviva Premiership summit.
But they were made to battle all the way by Worcester at Franklin’s Gardens last weekend before cutting loose to claim a 30-14 victory.
And Clark is expecting his table-toppers to face another stern test at Newcastle, who have lost their past eight league games.
“I don’t really care a lot for league tables and form because it doesn’t really owe you a lot when you’re out there on the pitch,” said the flanker. “It doesn’t really stand for anything.
“What we did know was that Worcester had a very close game against Leicester the week before we played them and they got a lot of belief from that.
“They came up to our place and pushed us in that first half.
“It was only in the second half when they lost some men that we were able to squeeze them and get more points on the scoreboard.
“Whoever you play in this league, you’ve got to prepare properly and play properly at the weekend.
“Newcastle have definitely improved. They’re a team who came up here and really tested us.
“Similar to Worcester up front, they put the squeeze on us and really challenged us at the breakdown.
“They’ll step it up at home, I’m sure. They’re coached to win those type battles and to really test us up front so it’s another week where we’re going to have to do the business.”