The goal broke the shackles for Urawa, who have been in free-fall with only one win in their last 10, with substitute Escudero scoring just seven minutes later. Just over 15 minutes later Brazilian striker Edmilson then put the game out of reach with two goals in two minutes.
The win will ease the pressure on under fire coach Volker Finke, with rumours surrounding his future put on hold for another week.
Spiranovic, who struggled for game time early in the season, restricted to games in the Nabisco Cup, has now started in Urawa's last seven games and seems to have cemented his spot in the middle of the Urawa defence.
After the off-season loss of Japanese international Tulio Tanaka to rivals Nagoya Grampus, Spiranovic looked like a natural replacement. However a small ankle injury just before the start of the season, couple with Urawa's winning form and Finke's resistance to change a winning line-up, thwarted Spiranovic's claims for a spot in the side.
But having proved his ability to get forward and get on the score sheet, a feature of Tulio Tanaka's game, Spiranovic now has a firm grip on the position.
With the Socceroos in action again in just 12 days against Switzerland and with new coach Holger Osieck set to announce his squad in the coming week, Spiranovic, who was left out of the squad for the Slovenia game earlier this month to sure up his spot in the Urawa side, will almost certainly be called up for just his fifth cap for Australia.
With the departure of Craig Moore leaving a vacancy in the middle of Australia's defence, and with Osieck, an ex-Urawa coach himself, just starting his reign, Spiranovic could not have timed his run of form any better.