The Blues picked up their third clean sheet on the bounce as they thumped Gillingham 4-0 in the Checkatrade Trophy last night.
The shutout made it just five goals conceded in eight games this season as Kenny Jackett's men continue to make defensive improvements.
Clarke feels the strides being made are evident to see.
He said: '˜The Carabao Cup wasÂ a bad resultÂ but the league is the main one, obviously, and this keeps it going.
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'˜We always fancy ourselves to score.
'˜So if we can keep it solid at the back as we are that's good news.
'˜We've started well with the results.
'˜The Luton game wasn't how we wanted to play.
'˜So we've been trying to move forward from that game and progress.
'˜If you've watched all of our games you'd see the progress we're making on the pitch.'
Clarke was the one starting constant from Saturday's Plymouth Argyle win as Jackett made 10 changes.
The 21-year-old was happy not to have a rest.
He added: '˜For me, I take it as a positive.
'˜I want to play every game and I want the gaffer to play me every game.
'˜I take it in my stride and if it happens again and again I'll take it.
'˜'˜Whoever plays out of our (central) defenders I fancy it's a good partnership.'