WXOS (101.1 FM) began broadcasting in the format Jan. 1 and has overtaken its two competitors, previous leader KSLG (1380 AM) and the longest-running of the entrants in the genre, KFNS (590), on the prime battleground — men ages 25-54. And 101.1's market share is nearly equal the foes' combined number.

In the Arbitron survey for the spring period, April-June, WXOS attracted 3.5 percent of those in that bracket who were listening from 6 a.m.-6 p.m. weekdays — the period they compete most head-to-head. KSLG, which had won the last three ratings "books,'' and KFNS were neck-and-neck but far behind. KFNS was at 1.9, KSLG at 1.8.

In the big picture, the overall sports audience grew substantially as WXOS took listeners from other formats rather than raiding KFNS and KSLG. The established stations had only slightly better market share last spring (2.0 each) than now. So sports radio went from 4 percent of the market then to 7.2 this time — an 80 percent gain.

"It's just a different beast on FM, because there's so much more audience available there to get,'' WXOS general manager John Kijowski said.

Before converting to sports, WXOS had broadcast Christmas songs for several months after switching from female-oriented music. While the move to sports was in the planning stages, Kijowski said he eventually wanted to be in the top five of outlets in all formats among men ages 25-54.

"The way I look at it, on Jan. 1 you started at nothing, at a zero rating, 33rd (last place among all St. Louis stations) then to 19th in the first book to 11th now'' he said. "It's an affirmation we're on the right track.''

KSLG general manager John Helmkamp said he's not surprised WXOS has taken the lead.

"I think we all expected that, especially early on,'' he said. "There will be a lot of people sampling, as happens with any new station in a format. The real test is whether they hold them."

In the last year KSLG has lost four men in key roles — Bernie Miklasz, Randy Karraker, Martin Kilcoyne and Jay Randolph Jr. And the contract with the morning show, KFNS' only program that led in its time block this spring, is up soon. It would seem vital that the station retain that if it wants to remain competitive.

"We're close'' to finalizing a new deal,'' Helmkamp said. "We're probably a week to two weeks away. We're both very close and I'm pretty confident we're going to get it done.''

Meanwhile, KFNS general manager Dave Greene said he's not a big watcher of the ratings.

"The numbers, good or bad, don't mean much to me,'' he said, adding "... we are much more than a radio station with print, interactive and promotions combined. We are the only station in St. Louis to offer that mix and the market is responding.''