Suburbs striker Noah Billingsley levelled, 1-1, in the 47th minute to trigger off a goal-scoring spree. Marko Stamenic hit a low drive between the legs of Blues keeper Joshua Hill in the 53rd minute before Logan Rogerson found the net with his head from a corner kick three minutes later and Ryan Feutz counterattack goal in the 76th minute resulted from the Rovers pushing up the park to play catch-up footy.
"It seems as if they've been given a rev up at halftime and they've come out at halftime to be a little bit more direct," James said, adding the hosts had expanded more energy than the Blues.
He felt the first goal "laziness", the second from a keeping error, the third one was earned and the final was expected when the Rovers had pulled out all the holds.
Suburbs now face bottom-placed Wairarapa United and Wellington United before signing off with Stop Out Sports Club and should, barring a huge upset, clinch the crown.
The Rovers have a relatively harder task, hosting mid-table campaigners Miramar Rangers and Lower Hutt City before closing their account against third-placed Wellington Olympic.
James was hoping the troops would keep their heads up with the cup quarterfinal beckoning against Albany United on August 3-4.
He said they had a squad of 17 adroit players and everyone had to put their hand up at training to show they wanted to be at the park.