Gary Wilson marked his first-class debut for the hosts with an impressive half-century as he showed excellent judgement to score 72 from 104 balls but three wickets from Buck ensured the honours were shared when rain forced an early close with Derbyshire 219 for 6.
And Buck is now hoping the County bowlers can keep the home side under 250 in the first innings.
“I thought we bowled well as a unit and put the ball in the right area although maybe a bit too short but we’ll be happy if we bowl them out under 250,” Buck said.
“It did a bit this morning but it still swung all day, we kept the ball in good condition, and we caught well again today.Four quick wickets in the morning and we should be alright.”
It could have been better for both teams as the initiative changed hands several times on a cool, overcast day when the County Ground floodlights were needed from the start of play.
The overhead conditions probably persuaded Northants to bowl first and there was certainly enough to suggest it was the right decision as the seamers went past the bat numerous times.
Ben Sanderson was the pick of the attack and was unlucky not to dismiss Luis Reece early on when the former Lancashire batsman, one of four Derbyshire debutants, edged just short of Ben Duckett at first slip.
Both Reece and skipper Billy Godleman displayed good temperament to bat deep into the first session before Sanderson deservedly broke through when he got one to lift on Reece who was caught off the shoulder of the bat at fourth slip.
Reece made only 19 but importantly for Derbyshire he had batted for 95 minutes to take the sting out of the bowlers although Sanderson gained another reward for his morning’s work when he moved one back just enough to trap Godleman lbw for 33.
The game appeared to have taken a significant shift towards Northants when two wickets in six balls early after lunch reduced Derbyshire to 114 for 4.
Rory Kleinveldt had struggled for a consistent line in the morning but he found enough away movement to have Wayne Madsen caught at second slip for 12 before Buck pinned Shiv Thakor lbw with the first ball of the next over.
For the next 25 overs it was about Wilson and Daryn Smit who also played soundly on his debut before he was squared up by Buck who then had Wilson lbw playing across the line before bad light and rain ended play.
“It was important that we fought hard and I think it was a pretty even day, “ Wilson said.
“It will be an important first hour in the morning and if we can battle on and get as close to 300 as possible, I think we’ll be in a good position.
“When I came to the wicket they had just gone ‘bang, bang’ so we had two new batters at the crease but we knew that if we absorbed some pressure and could counter a little bit we would be in a good position if we managed to come through that.”