The 18th annual 3M Half Marathon on Sunday morning was a race all about changes. For a race with such a long and distinguished history, changes are always risky but 3M passed with flying colors.

First, the course changes. The revised 3M Half retained the downhill flavor and much of the terrain of its north-to-south course, but if anything the new course is faster. The finish up MLK to the Bob Bullock Museum certainly added a new element, but the finish area is much nicer and logistically more convenient than Waterloo Park.

The other big change was the lack of an elite, national-class field. No problema. Few in the sold-out field of 6000 seemed to miss the international runners. Instead of interlopers coming in and snatching the prize money, this year the bulk of the $18,500 that 3M put up, stayed in local hands.

And the locals didn’t disappoint. Austinites Scott Rantall and Kelly Williamson both scored impressive wins.

Rantall, the 30-year-old ex pat from Geelong, Australia, dominated the men’s division in his final tune up before the Livestrong Austin Marathon by winning in 67:14. Williamson, a professional triathlete, had a huge day. The 34-year-old, who swam collegiately at Illinois, had a massive PR of 1:14:42 to vanquish the women’s field.

Oh yeah. One other change—the weather. Last year, the 3M field suffered in warm humid conditions and the times reflected that. This year? Race conditions could not have been more ideal with temps in the high 30s at the start, low humidity and not even a hint of a breeze.

“I thought it was perfect out there,” said Williamson, who did a mini-taper for 3M by actually not riding her bike for three days. “My goal this morning was to be aggressive and try to run 5:45-5:50 pace right from the start and finish strong.”

Mission accomplished. Williamson teamed up with 42-year-old Chris Kimbrough in the early miles (going through 5-K in 17 minutes), but the two still trailed Jess Barton, a 22-year-old triathlete from Massachusetts, who ran at Northeastern University.

Barton took off at a blistering pace, but it was a bit too rich. At the 5-mile mark, Williamson began to reel her in. “I just wanted a solid race this morning. But I was definitely after a PR.”

So was everybody else. Williamson’s winning time of 1:14:42 wasn’t just better; it busted her previous best by a wide margin. Williamson, who is one of the best runners among the top professional triathletes, usually runs in the 1:17-1:18 neighborhood in 70.3 races. But her open PR was “only” 1:16:58, set last January in the USA Championships in Houston, just a notch better. (She should have ridden her bike to Houston.)

Her 3M time was more than two minutes faster than her previous best which brought a huge smile on Williamson’s face. “I’m very happy with the way I ran. I think it will definitely give me some momentum going into my triathlon season.” Her tri season begins next month in Panama with a 70.3 and hopefully, concludes in Hawaii in October with the Ironman World Champs.

Barton held on for second in a fine time of 1:15:52, while Kimbrough settled for third (first masters) in 1:16:20.

The men’s race was much closer than women’s. A pack of four formed at the front, including Rantall, Tialoc Mancilla, Joseph McCellon and Alex Cameron. Said Rantall, “The early pace was up and down. My plan was to sit back and let the other guys wear themselves out.”

Which is exactly what he did. Although the leaders took off at five-minute pace on the early flat section of the course, Rantall was content to remain patient and wait his turn.

“I didn’t want to lead early,” said Rantall. “I knew all along that if I had to, I could run a 4:40 last mile.

But he didn’t have to do quite so much. The first 10-K flew by in 31:41 with Mancilla maintaining a short lead, but two miles later along 45th Street, Rantall pulled up and the two ran shoulder-to-shoulder until making the swing onto Duval.

After the turn onto Duval and the long, gradual downhill, Rantall finally made his move at about 11 miles and within a half mile, gapped Mancilla. Then, on the final steep downhill to DKR, Rantall opened up even more room and the race was essentially over and done with.

Rantall’s time of 1:07:14 was more than a minute slower than his PR of 1:06:03, set last year at the Gold Coast Half Marathon in Surfers Paradise, Australia, but was definitely pleased with his effort.

“I had a plan and executed it,” said Rantall who manages the Rogue store in Cedar Park. “Anytime you can do that, you have to be happy.” Next up for Rantall is the tough Livestrong course in three weeks and his goal is in the 2:25 neighborhood, about five minutes slower than his best.

Also running Livestong will be McCellon, the former Texas Tech runner who is originally from Alvin. Now living in Austin where he manages the bar at Chez Nous, McCellon has been the most consistent runner in the Austin Fit Magazine Distance Challenge.

Although he finished behind Mancilla (1:07:30) in third in 1:07:43, the tall Texan was thrilled with a three-minute PR. “I’m looking forward to Livestrong,” said McCellon. “The only other time I’ve done a marathon was when I paced somebody so Livestrong should be interesting.” After Livestrong, McCellon plans to run Boston.

The 3M Half Marathon was the fourth race in the Austin Fit Magazine Distance Challenge. Next up on February 19th is the big enchilada—the Livestrong Austin Marathon.