Wanderers hosted Posh at the University of Bolton Stadium and went close to taking the lead in the first half when Gethin Jones headed against the post. Conor Bradley had earlier seen a good chance go wide.
After the break, Dion Charles curled over from outside the box, while Jack Iredale also saw an effort saved. But Wanderers went ahead thanks to Dapo Afolayan as his deflected effort bounced over the line to deliver the hosts a valuable three points.
Wanderers remain fifth in the table but have consolidated their place in the top six with the victory. They are four points from top spot as things stand.
During the encounter, Wanderers boss Evatt was able to throw on Afolayan, Kieran Sadlier, Amadou Bakayoko and Jon Dadi Bodvarsson from the bench. Speaking on the EFL Highlights show on ITV4 as a pundit, former West Ham, Norwich City and Crewe Alexandra striker Ashton believes those changes made the difference in the end and illustrated the strength in depth in Bolton's squad.
Ashton said: “They're not scoring the goals, Peterborough, that is what they are, they score goals. They're not a team that's ever really kept loads of clean sheets.
“The goals have dried up and I thought the aggressive four substitutions that Ian Evatt made just made the difference in the end. The most joint clean sheets as well so if you're shot shy, it's a difficult place to go.
“It made the difference in the end. It made me think their squad looks strong, Bolton.”
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