On Saturday, 10,000-plus fans are expected outside the Walker again for Rock the Garden. Tickets were gobbled up within an hour for the most local lineup ever. It's also the most significant sign yet that 89.3 the Current is now the most powerful music broker in town.

Four of Saturday's five RTG bands hail from the local club scene, including New York-based the Hold Steady. Two of the other locals, Trampled by Turtles and Doomtree, are on tour this summer playing some of the country's biggest festivals. The fourth, Howler, is too young to even know what the scene was like pre-Current.

From 1998 to 2004, RTG lineups drew 1,500 to 3,000 fans. Then along came the Current. While the Walker Art staff can take credit for picking Saturday's lineup, it's clearly because of the Current that 10,000 fans jumped at the chance to go.

"It has completely been a game-changer," First Ave general manager Nate Kranz said of the Current. "Just look at all the sold-out spring shows we had," referring to first-time headlining Mainroom gigs by the 4onthefloor, Lucy Michelle & the Velvet Lapelles and Caroline Smith & the Good Night Sleeps. "None of those would have sold out without the Current."

Doomtree's Chicago-based manager, Doug Lefrack of Feisty Management, acknowledged the early press and fan support for the hip-hop group and its members' solo careers. But when the Current put the group in steady rotation, he said, "That's really when all the doors started opening." And he didn't mean just locally.

"I know for a fact that the other noncommercial stations around the country that have played the 'No Kings' album started doing so because the Current was playing it," he said. "Minneapolis is such a strong music scene in general, the Current just sort of amplifies that. You don't see that kind of relationship between the scene and a radio station in 99 percent of the other markets out there."

The Current's program director, Jim McGuinn, who came to the station from Philadelphia four years ago, acknowledged that the staff takes a lot of flak over the stuff it chooses not to put into rotation. Said McGuinn, "We give negative reviews by omission."

And there's a lot of local music that's not getting played on the Current. McGuinn provided stats that prove just how much is getting played, though: More than 15,000 rotations were split between roughly 600 local acts (of all eras) on the station in 2011. Of those 600 acts, about 40 were played more than 100 times, i.e. in regular rotation.

However many local acts wind up with frequent 89.3 spins this year, you can bet that four of them are performing Saturday outside the Walker.

Rock the Garden: The lineup

Howler (3:45 p.m.)

Frontboy Jordan Gatesmith's scene-trashing interview with a BBC blogger didn't earn him many local fans, but this gig and Sunday's tribute to his late neighbor, Karl Mueller of Soul Asylum, should. Not that he needs us. Gatesmith recently updated his Facebook page to show he's dating former Smiths guitarist Johnny Marr's daughter, and he will earn more British love at the Leeds and Reading festivals in August.

tUnE-yArDs (4:30)

The only non-Minnesotan singer on the lineup, face-painted, drum-banging New Englander Merrill Garbus almost deserves resident status for how incessantly the Current has played her urban-grind single, "Gangsta." She and her idiosyncratic, horn- and percussion-wired ensemble also deserve props for a lively sold-out First Ave show in November.

Doomtree (5:45)

The rap crew just finished its first European tour and is soon headed overseas again for a couple of festivals. Its members are otherwise busy with individual projects, including new albums by P.O.S. (out Sept. 18), Dessa and Paper Tiger.

Trampled by Turtles (7:15)

Bonnaroo last weekend. Newport Folk Fest in July. Lollapalooza in August. Maybe a third late-night TV gig somewhere in there (the Duluth string band's Letterman debut in April was a slam dunk). Talk about a constructive summer. Minnesota fans who didn't get RTG tickets will have to head to Wisconsin to hear songs from the new album "Stars and Satellites" this summer, be it Big Top Chautauqua on Friday or Somerset on Aug. 10.

The Hold Steady (8:45 p.m.)

Still easing their way back from a first-ever extended hiatus last year, in which time Edina-bred frontman Craig Finn issued his solo debut, the New York-based Midwesterners will have new songs to premiere from an album due early next year.