The win gave P.E.I. a split of the New Brunswick Junior Baseball League doubleheader and improved its record to 15-7.
The Islanders big inning was keyed by a bases loaded triple from Connor McGregor and a two-run double by brother Curtis McGregor, who had three hits.
Connor McGregor had two hits while Ryne MacIsaac and Riley Gallant both went 1-for-2 with three runs scored.
On the mound, winning pitcher Jayden MacLean and Connor Jones combined to allow only three hits and struck out four.
Jeremie Arsenault and two relievers gave up nine hits and 10 walks for Metro. Nick Leblanc had a two-run single for the Mudcats.
In Game 1, Mudcats starter Nate Ronan and Isles starter Porter Smith hooked up in a pitchers duel.
Jesse Malone's RBI double plated the games only run in bottom sixth in Metros 1-0 win. Blake Flinn stranded the tying run on third in seventh to earn the save.
Smith surrendered five hits and struck out five.
Declan Buckle had two hits for Metro while MacIsaac, Curtis McGregor, Logan MacDougall and Chasse Gallant each had hits.
P.E.I. wraps up regular season play Saturday with a doubleheader in Fredericton, N.B.