The home side go into day four on Sunday on 149 for three in their second innings, still 48 behind the County’s first innings 390 having been asked to follow on.
They had been in big trouble at 58 for three, but a stubborn unbroken partnership of 91 between Paul Walter (40no) and Matt Critchley (44no) has given Essex hope of avoiding defeat.
The pair’s efforts came off the back of an equally important rearguard action in the morning session, as Essex recovered from their overnight 95 for eight to post 193 all out in their first innings thanks to a career-best 75 not out from Sam Snater.
But there is no doubt Northants are still in the ascendancy, and Sadler is confident his players can finish the job on Sunday.
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“Where we are now we are still on top, we’re still in the box seat and we’re in a great position,” he said.
“Credit to them, they played well that last hour and a half.
“We know it is going to be tough, it’s first division. If you’re going to win first division games it’s going to be hard.
“But come back fresh in the morning, a couple of quick wickets – they’re still trailing us by 45-50 – and we’re in a great position. My lads were superb on Saturday.”
Sadler admitted there had been discussions in the Northants camp at lunch as to whether or not they should enforce the follow on, having earned a 197-run first innings lead.
“We chatted away about the follow-on,” said the head coach.
“The earlier we got those two wickets the easier it would have been to make them follow-on.
“We felt we’d control the game this way with the bowlers who were fresh enough to continue.
“We had six bowlers to keep rotating and we felt this was the best way to put them under pressure.
“Yes, they’ve won that last session but they’re still under more pressure than we are. That was the discussion and good teams have to do it the hard way sometimes.
“There’s still a little bit in the pitch for us and we’ve got to hang in there, stay patient and get a couple of wickets.
“As Geoffrey Boycott used to say, put two on the scoreboard and all of a sudden they’re still behind us and five down.”
Sadler will be hoping that all changes on Sunday morning.