YAKIMA -- When Clayton Chumley was not yet 2 years old, he would stand outside the fence bordering his father's pasture and call out "Doc! Doc!"

One of the bulls in the pasture, a muscular, 1,700-pound Red Brangus, would lift its head at the sound of the boy's voice, leave the other bulls behind and amble over. Once at the fence, he would lower his head against the fence rails, allowing tiny Clayton to pet him.

More than two years later, Rod Chumley, Clayton's dad, still loves that memory.

He also loves that Doc -- known to bull-riding fans around the continent as Doctor Proctor, in their parlance one of the "rankest" bulls on the Professional Bull Riders circuit -- is not remotely rank outside the bull-riding arena.

When Chumley went to the pasture edge on Tuesday and beckoned for him -- calling out, simply, "Doc!" -- the bull came out of the pack of bulls in the pasture, trotted over, then walked right past Chumley into the chute leading to his pen.

"If you tried to do that with a lot of the others," Chumley said, "they'd hook you, knock you down and camp out on you."

Some bulls want to do that to every bull rider they buck off. Some might try it at tonight's Professional Bull Riders Enterprise Tour event at the SunDome, where 40 bull riders will try to earn a berth in the 10-rider "short round" finale.

Not Doctor Proctor, whose appearance in tonight's fourth section at the SunDome will be his last; Chumley and his partners plan to pull the bull from competition.

"He won't hook you or try to hurt you," said Cody Ford, who was the first bull rider ever to climb aboard Doctor Proctor and will also be in Saturday's PBR event. "He's dang sure real nice to be around, doesn't try to be mean or knock fences down."

The bull then known as K23 was just one of 16 bulls Chumley and a partner, Sorrell Katich, bought as a set five years ago, and it wasn't until Ford tried to ride him three years ago in Chumley's practice arena that they truly recognized his potential. Ford was a 16-year-old phenom from Stanfield, Ore., who would go on to become the national high school bull-riding champion.

That day, though, the bull was the champion.

"It lasted about one jump," Chumley recalled. "Doc pretty well drilled him."

"He bucked as hard then as he ever did, I'll tell you that," Ford says. "I made a couple rounds on him -- not a long ways, maybe three or four seconds. I got on him three or four times there (at Chumley's arena). I dang sure knew he was something special."

Ford was right. Over Doctor Proctor's first two years on the PBR circuit, he went unridden through his first 30 "outs." The eight cowboys who have stayed on him in his 59 PBR rides have averaged nearly 89 points -- as score that virtually assures a finish in the money.

ProBullStats.com, a site that chronicles bull riding on every circuit, assigns bulls a "power rating" based on its average judges' marks and the rate at which it bucks off its riders. According to its numbers, a bucking bull with Doctor Proctor's sustained power rating comes around only once every 1,548 bulls.

For his swan-song performance, Doctor Proctor is scheduled to be the final bull of the 40-ride, four-section long round, with the top 10 advancing to the short round. The bull rider who drew the good Doctor is 23-year-old Brandon Wallentine of Paris, Idaho.

"I'm pretty excited," Wallentine said Thursday after learning of the draw. "I've been waiting for this opportunity for quite a while. I've seen him a few times, and been wanting to get on him. He gets so much air (on his jumps), I think it'll be a real fun time."

The PBR is counting on it, too, though there will plenty of other bulls worth watching tonight. Flying Diamond's Bearcat is still unridden after 19 outs; Big Bend/Flying 5's Firewater has been selected to both the PBR Finals and the PRCA's National Finals Rodeo; and another Chumley bull, Hard Water, already looks like a future bovine superstar after only three outs.

"I feel sorry for whoever draws Hard Water," said Mike Wright, another Selah rancher who was helping Chumley cull out his bulls for tonight's PBR event. Noting that none of Hard Water's three would-be riders has lasted longer than four seconds, Wright added, "Nobody's even warmed him up."

In all, Chumley will have seven bulls in tonight's event. But he'll always have a soft spot in his heart for the bull he and a partner, Sorrell Katich, bought five years ago for only $6,000. Buyers have offered Chumley about 100 times that amount for Doctor Proctor since then, but Chumley's answer has remained no.

"I turned it down for the love of the bull. He's going to die right here," he said. "He put me on the map, Doc did. I went from just bucking bulls to the top in one year. He's the start of it all. We're going to have several superstars out in that pasture, and they'll all make money.

"But there's only one Doc."

If you go

What: Professional Bull Riders Enterprise Tour stop.

When: 7 p.m. today.

Where: Yakima Valley SunDome.

How much: Ticket prices $45, $32 and $12, available at State Fair Park box office and at the door.