London-region "garage rock" bands continue to battle for the chance to open a concert, where about 4,000 fans are expected. Tomorrow, in a 19-and-up show at the Embassy, more than 10 unsigned bands become the final London region outfits to compete for that chance.

Many of the bands at the Embassy show and earlier battles in the same series have long since graduated from the garage practice space of rock lore and played clubs or even recorded. But they're all chasing the same goal of opening a big show.

Voting by fans at a club on the night of the battle helps identify qualifying bands.

The qualifying band gaining the most Internet votes at www.iam.ca earns its spot on the 19-and-up Molson-sponsored bill at a Western Fair stage with Canadian rockers Default, I Mother Earth and Kazzer on June 15.

That show is a Molson pass-only event.

About 4,000 fans are expected at that show, one of a series across Canada under the Molson Canadian Rocks House Party label.

Bands from 14 regions across Canada have been competing for similar chances at House Party shows.

With the introduction of a battle-of-the-bands component, local grassroots bands will be opening up each show for their home-town crowds.

"We're adding local 'garage bands' to each event to really get people out there and enjoying what's going on in their cities," says Sean Moffitt, marketing vice-president for Molson Canadian.

"(It's) an amazing opportunity for independent bands to get some serious exposure at high-profile shows," Moffitt says.

The Embassy gig is the final one of five in the London-Windsor region. An earlier battle at London pub Molly Bloom's last week has left London punk rock band Angry Agency leading London-Michigan band Ruth's Hat in iam.ca voting.

After tomorrow's Embassy showdown, fans have seven days to log onto iam.ca and vote for act they felt "rocked the house." The eventual London-Windsor region winner of the garage band competition is expected to be announced next Wednesday.

IF YOU GO

What: Battle of bands for a chance to gain a spot on a Molson Canadian Rocks House Party bill later this month; winning band at end of Internet voting gets opening spot on the 19 and up Molson- sponsored bill outdoors at Western Fair with Default, I Mother Earth and Kazzer at the Youth Talent stage, just north of the Progress building; that show is on June 15, with gates opening at 6 p.m.; fans for that show win passes through Molson-connected promotions, contest and giveaways; check www.iam.ca or call 1-800-MOLSON1 (1-800-665-7661).

When: Tomorrow; doors at 7 p.m.

Where: Embassy, 732 Dundas St., London

Lineup: In order of appearance, battlers are listed by Molson as: 19 Days, Phantom Black, Red Splendor, Johnny El Camino, Spearhed, Penfield, Chrome Naked, East Wing, Driving Lester, Popjoy and Never Seems Happy

Tickets: $10; 19 and up; call 434-6604