The hosts did not have a game in mid-week and arrived at the Banks’s Stadium having had an extra break.
Walsall, on the other hand, were playing their third game in a week and after a tight affair Clarke believes the schedule played a part - but also felt a draw was a fair result.
“It was role reversal from last season’s games, there was respect from both sides,” he said.
“They have players that can hurt you and are lucky for that little bit of quality.
“I think you could tell it was our third game in a week, they were a bit more fresher at times, but I thought we created the better chances.
“Eli (Adebayo) has had his great header saved, Paddy (Emmanual Osadebe) has had his chance in the first 10 minutes.
“It was a cagey affair but I thought it was two good teams cancelling each other out.
“I asked for a clean sheet today. In this run of 10 undefeated, now 11, we’ve only had two clean sheets in that.
“I knew they were an attacking threat and will cause problems. They’ve scored a lot of goals, like ourselves.
“Two good teams cancelled each other out on the day but with the clean sheet I thought we defended superbly as a team.
“Probably the biggest disappointment for me on the back of the week is that it should have been seven points really.
“Colchester should have been three shouldn’t it. We’re undefeated but it’s early days yet.
“What I will say is, and I’ve said it to my players, there’s going to be so many games in this six month spell.
“It’s going to be the ones that apply themselves and look after themselves. The best squads are the ones that can handle it better. Have a mixture and freshness at the right time.
“Making sure that the players know their jobs when they come into the side.”
Exeter lost out on promotion through the play-offs last season, falling at the final at Wembley and Clarke insists that Matt Taylor’s side will challenge again this campaign.
“They were always a constant threat, they have good wide players - they have good players,” Clarke added.
“For me, I thought it was a side that would have got in the top three last year if it wasn’t curtailed.
“We have respect for Exeter, I think they’ll be there amongst it this season but it goes to show how far we’ve come that we’re disappointed at not winning the game against a good team.”
Meanwhile, Clarke is pleased to have added depth to his squad with Adan George and Jake Scrimshaw joining on loan after Josh Gordon’s injury.
“We’ve added two centre forwards and we’re really thankful of Bournemouth and Birmingham because of the financial situation,” Clarke said.
“For those to allow two of their good prospects is testament to the good side of football.
“We’re pleased to freshen up the front line, it gives us a few more options.
“Adebayo and Lavery are top centre forwards for me but we need something behind them with Josh injured.
“We have two fit centre forwards so you need that depth in your squad.”