Brandon Hynick’s pitching motion could fit in an airplane bathroom.

A short step back, tiny swivel with the hips, five-inch slide step forward and a straight up-and-down release. It’s quiet, but it’s been more than effective — perhaps too much so — this season.

“I feel the simpler it is, the easier it is to repeat,” said Hynick, who at 9-7 with a 3.57 ERA has been Sky Sox’s best pitcher and whose perfect game was the highlight of the year for the Rockies minor-league system.

But there’s a reason so many pitchers with great “stuff” — Justin Verlander, Tim Lincecum and Ubaldo Jimenez to name a few  — need room to work. Those wild leg kicks generate power from the pitcher’s lower half, the key to velocity.

“When I watch film I can really see that I need to use my legs more,” said Hynick, whose fastball sits in the upper 80s, occasionally peaking out at 91 or 92 mph. “It’s a work in progress.”

At 6-foot-3, 205 pounds, still just 24 and with impeccable control (107 walks in 551��” minor-league innings), Hynick would seem the perfect lump of clay for the Rockies’ system to shape into the type of pitcher they want.

“He’s a sponge,” Sky Sox pitching coach Chuck Kniffin said. “He’ll take in as much information as we give him.”

The question: Are a couple of miles per hour worth messing with a good thing?

Since a rough April, Hynick has gone 8-5 with a 2.81 ERA in the hitting-dominated Pacific Coast League heading into today’s start. He’s thrown seven scoreless innings in five starts this year and has three other outings in which he’s gone at least six innings and given up just one run.

This is Hynick’s fourth pro season, his first two saw him earn his league’s top pitching honor and last year, much like this, saw him rebound from a tough start and be his team’s top starter.

A quick glance at his contemporaries shows results clearly aren’t enough in the minors.

Jhoulys Chacin, who had similar numbers at the lower levels, bypassed Triple-A last month when the Rockies placed him in their bullpen. Esmil Rogers, who hasn’t achieved Hynick’s success, recently advanced from Double-A to the Sky Sox rotation and Colorado general manager Dan O’Dowd said he believed Rogers would be promoted again this year.

The difference between Hynick and Chacin and Rogers? The latter pair can light up a radar gun and post big strikeout numbers.

Hynick’s strengths — intelligence, command and an ability to work in a hurry — might be compromised with a complicated motion that adds velocity but forces him to think about things other than pitch sequence and the hitter’s tendencies.

Kniffin, who believes Hynick is deserving of a September call-up, said the right-hander can take the repertoire he has right now — which includes a fastball, curveball, split-fingered fastball, cutter and change-up — and be successful at the next level with a minor adjustment that doesn’t include a mechanical change.

“He’s around the plate so much that he just needs to be able to work off the plate,” Kniffin said. “And I don’t mean just off the plate like a couple of inches, I think he needs to be comfortable working well out of the zone.”

Hynick is aware of all this. He also knows the Rockies are contending for a playoff spot and may want as many role players or innings eaters as possible when major-league rosters expand in September.

“I’ve thrown out of the bullpen twice in the last five years,” he said. “But if that’s a role that they want me to be in — hey, I’d be happy to take anything.”

Sky Sox pitcher Brandon Hynick chatted with Pacific Coast League president Branch Rickey III before being honored Friday for his perfect game earlier this season. Photo by KIRK SPEER, THE GAZETTE