Seventeen wickets tumbled on an eventful opening day as Northamptonshire hosted Yorkshire in the LV= County Championship First Division.
Ian Butler was the pick of the hosts' attack as Yorkshire were first bundled out for 136 in 40.3 overs.
Northants then fared moderately better, thanks to 70 from James Middlebrook, as they reached 191 for seven before the close.
Yorkshire's day began badly as Adam Lyth fell lbw for a duck with just four runs on the board by Maurice Chambers, who finished with two for 23.
Lyth was one of three Yorkshire batsmen to fail to trouble the scorers, including captain Andrew Gale and Tim Bresnan, who arrived at Wantage Road after being released from England duty. The latter pair both succumbed to Butler, who returned impressive figures of 4-41.
— Northants Cricket (@NorthantsCCC) May 31, 2014
Yorkshire lost wickets at regular intervals but new signing Aaron Finch offered hope of a revival, hitting four fours and a six on his way to a top score of 34.
His efforts were ended when he played on to Azarullah to leave Yorkshire 95 for seven in the afternoon session.
Azarullah went on to claim 3-41 but it was Maurice Chambers who finished the innings when he ended Liam Plunkett's breezy late resistance at 25.
Yorkshire reprieved Middlebrook early in Northamptonshire's reply when he was dropped by Finch on 10 off Bresnan.
Jack Brooks made the first breakthrough when he had captain Stephen Peters taken at slip by Alex Lees after an opening stand of 44.
Brooks then snared David Sales, Matthew Spriegel and Rob Keogh in quick succession on his way to 4-58 to reduce his old club to 90 for four at tea.
Middlebrook batted on to reach his half-century off 70 balls, with nine fours, but he survived a scare on 59 when Lyth was unable to take a difficult chance at second slip.
Middlebrook gone! He's bee caught at first slip for well made 70 by Finch off Bresnan. Northants are 138-6.
— Yorkshire CCC (@Yorkshireccc) May 31, 2014
Bresnan trapped Rob Newton leg before to end a promising fifth-wicket stand of 39 with Middlebrook, whose luck then ran out when he edged the same bowler to Finch at slip.
After a stoppage for bad light in the evening, Plunkett then dismissed Andrew Hall lbw before the close, leaving Ben Duckett and Butler looking to extend a lead of 55 on Sunday.