The visitors arrived without their first-choice opening bowlers and it showed as Town piled up 290-6 in their 50 overs.
Opener Chris Milner top scored with 70 for Town before gifted teenager Sulemain Saleem struck a run-a-ball unbeaten 54.
Mark Edwards then claimed 5-38 in 10 overs, largely spent practicing his bouncer as Rushden were rushed out for 127.
Peterborough Town seconds sealed the Division Two title last weekend easily picking up the three points they required from their final game at Great Houghton.
Youngster Sam Jarvis has enjoyed a first full season for Town and it continued with an innings of 91 not out in a team total of 220-5. Stuart Williams also batted well for 54 before Sreehari Subramonian claimed 4-39 as Town completed a 48-run victory.
And it could be a title treble for Town who retained their unbeaten record in Rutland Division One with a nine-wicket stroll against Burghley Park at Bretton Gate yesterday.
Sulemain Saleem enjoyed a rare bowl and took 4-32 in nine overs as Burghley were despatched for 111. Scott Howard (51no) and Karanpal Singh (34) batted briskly to ensure Town picked up maximum points.
Bourne sealed their first Lincs Premier Division title since 2014 with a game a to spare despite losing at home to bottom club Woodhall Spa. The seven points they picked up made them uncatchable. Pete Morgan (59) and Robert Dunn (52no) batted best in Bourne’s 212-7 in reply to Woodhall’s 235-7.
Market Deeping have lived in their neighbour’s shadow all season and their ordinary ssummer continued with a three-wicket defeat at Scunthorpe. Connor Gillett struck 103 for the losers.
Wisbech crashed from 53-0 to 108 all out as they lost their Cambs Division One play-off semi-final by 93 runs at Eaton Socon who go on to play Histon in the final this weekend. George Gowler and Josh Porter claimed three wickets apiece for Wisbech.
Castor and fford Park both finished their Cambs Division Two seasons with wins.
Northants Premier Division
Peterborough Town 290-6 (C. Milner 70, S. Saleem 54no, Josh Smith 43, L. Bruce 28) beat Rushden 127 (M. Edwards 5-38, L. Bruce 2-9) by 163 runs.
Northants Division Two
Peterborough Town 2nds 220-5 (S. Jarvis 91no, S. Williams 54) beat Great Houghton 172-8 (S. Subramonian 4-39, V. Mangat 2-25)
Lincs Premier Division
Woodhall Spa 235-7 (O. Caswell 64,B. Wright 3-42) beat Bourne 212-7 (P. Morgan 59, R. Dunn 52no) by 23 runs.
Scunthorpe 261-7 (M. Carter 139, A. Green 3-52) beat Market Deeping 259-5 (C. Gillett 103, J. Hook 63) by 3 wkts.
Cambs Division One play-off semi-final
Eaton Socon 201 (J. Carpenter 93, J. Vale 57, J. Porter 3-23, G. Gowler 3-37, G. Freear 2-41) beat Wisbech Town 108 (G. Freear 25, D. Haynes 23, J. Dawborn 4-31) by 93 runs
Cambs Division Two
Castor 159-8 (R. Smith 47, A. Killingsorth 36no) beat Saffron Walden 2nds 156 (R. Evans 3-27, S. Johnson 2-11, S. Dockerill 2-37) by 2 wkts
Ufford Park 236-8 (A. Larkin 40, J. Harrington 39, W. Javed 33no, beat Foxton 2nds 122 (W. Javed 2-23, M. Stephenson 2-42) by 114 runs.
Rutland Division One
Peterborough Town 112-1 (S. Howard 51no, K. Singh 36) beat Burghley Park 111 (A. Murphy 25, S. Saleem 4-32, S. Jarvis 2-23).