Whitworth took the local bragging rights in the ChromaSport United Counties League Premier Division as they beat Rothwell Corinthians 2-1 at London Road.
Goals from debutant Nathan Burrows and Cavell Jarvis sealed a fourth league win of the season for the Flourmen as Corinthians were condemned to a third defeat in a row.
Desborough Town were held to a 1-1 draw by Boston Town at the Waterworks Field.
John Dean fired Ar Tarn into the lead after 26 minutes but the visitors earned a share of the spoils with an equaliser just past the hour.
Wellingborough Town slipped to a 2-1 defeat at high-flying Daventry Town.
After a goalless first half, Tommy McGowan and Jake Dumbleton put the hosts 2-0 up.
Mark Pryor pulled one back from the penalty spot but the Doughboys were unable to find an equaliser.
Raunds Town had their lead at the top of Division One cut to two points as they were held to a 1-1 draw by Melton Town at Kiln Park.
The Shopmates fell behind but earned a share of the points thanks to Jamie Russell’s goal on 65 minutes.
Second-placed Pinchbeck United closed the gap with a 3-1 victory over Irchester United, who had Ryan Lovell on target.
Burton Park Wanderers returned to winning ways as they beat Oakham United 4-2 at Latimer Park.
But it was a bad day for Thrapston Town who went down 3-0 to Bourne Town at Chancery Lane and for rock-bottom Stewarts & Lloyds, who were sent to their 15 defeat in a row when they lost 2-1 at Harrowby United.
Rushden & Higham United suffered a shock 3-0 home defeat to Northants Combination Premier Division side Wollaston Victoria in the second round of the NFA Junior Cup at Hayden Road.