It was the Scots who almost made the perfect start as Ryan Stevenson wriggled free in the box in the second minute but the forward could only drag strike wide. Nzuzi Toko was the first to threaten for Albion but his effort from distance dragged safely wide.
Scott Fox was the first keeper called into action and Thistle were indebted to him for keeping the scores level. Kemy Agustien’s sublime diagonal ball over the top was met by Craig Mackail-Smith only for Fox to excellently tip the striker’s volley around the post.
As the half wore on Albion began to exert more control and Agustien was the provider again, teeing up Inigo Calderon who saw his goalbound drive bravely blocked by Conrad Balatoni. Partick responded and Kallum
Higginbotham’s cross looped up onto the bar and Christie Elliott picked up the rebound but Jake Forster-Caskey threw his body on the line to stop the midfielder’s powerful shot.
Solly March fizzed an effort wide from distance, but it wasn't long before the youngster made a telling contribution as the midfielder picked an inch-perfect ball over the top to Mackail-Smith, and the forward took the ball in his stride with one touch to control before firing home with aplomb. Gordon Greer then doubled the Seagulls' advantage on the stroke of half-time with a close range header fro a Jake Forster-Caskey corner.
Hyypia shuffled his pack at the break making six changes but it didn’t affect Albion’s momentum that had built before half time, as Rohan Ince went close with a header and March lobbed the ball over the on-rushing Fox with his effort dropping just wide.
The Seagulls didn’t have to wait long for a third as half-time substitutes Charlie Harris and Shamir Fenelon combined with the latter heading in Harris’s brilliant cross for his third goal of pre-season.
Elliott threatened to reply for Thistle but Christian Walton comfortably dealt with the strike before Harris produced a moment of brilliance as he thundered in off the bar from 25 yards to make it 4-0.
Harris went close to a second, as he fired another long-range attempt just wide of the post, and Fenelon saw a shot blocked after a rampaging run from midfield by Ince.
Albion's only negative was seeing Lewis Dunk limp off late on in the game, but Hyypia - vocal from the bench throughout - will be delighted to have seen his charges hit nine without reply in their first two friendly matches.