Jon looks set to clinch the outright record in Glasgow's last league match of the season against Neath/Swansea Ospreys next week.
JP returns as captain at No.8 after missing last week's defeat to Llanelli, with Paul Dearlove switching to the blind-side flank in place of Andrew Wilson.
Graeme Morrison also returns, taking over at outside centre from David Millard, who impressed last week, grabbing the try that gave Glasgow a deserved bounus point.
Three of Glasgow's four props – Euan Murray, Andrew Kelly, and Lee Harrison – are unavailable because of injuries so two props have been called up from club rugby. Ben Prescott, the Aberdeen GSFP prop who played as a replacement last week, will be at loose head in place of Kelly, and Glasgow Hawks' Eric Milligan will be on the bench.
Prescott will be making his first start for Glasgow, though he has appeared four times as a replacement since 2001, and Milligan was in Glasgow's nominated European squad for the Parker Pen Challenge Cup competition and led Hawks to BT Cup victory last weekend.
It is hoped that Murray, who has a thigh injury, and Kelly will be fit for the match against Ospreys next week.
Rory Kerr misses out because of the head knock he sustained early in the Llanelli match. His replacement there, Glenn Metcalfe, remains on the right wing.
Glasgow
15 Moffat">Stuart Moffat
14 Glenn Metcalfe
13 Graeme Morrison
12 Andrew Henderson
11 Sean Lamont
10 Dan Parks
9 Sam Pinder
1 Ben Prescott
2 Scott Lawson
3 Matt Proudfoot
4 Joe Beardshaw
5 Andrew Hall
6 Paul Dearlove
8 Jon Petrie
7 Donnie Macfadyen
Replacements from Gordon Bulloch, Eric Milligan, Rory McKay, Roland Reid, Andrew Wilson, Graeme Beveridge, Calvin Howarth, David Millard