LOWELL -- When Ryan Clark is at his best in the ring, boxing isn't much of a contact sport.
He views every fight as a six-minute endurance test. It's an ultimate survival of the fittest battle, where Clark is constantly on the offensive, sticking, moving and most important of all, slipping punches.
Clark started fast Tuesday night and continued to gain speed over the course of three rounds while earning a hard-fought decision over Gabriel Pineda of Waltham in a 152-pound Novice Division Greater Lowell/Central New England Golden Gloves quarterfinal bout at the Lowell Memorial Auditorium.
"His strength is his offense," said Clark's trainer, Linda Murphy. "He always has energy and he keeps going. He's tenacious. He wears opponents down. He didn't allow his opponent to get anything off tonight. He stayed on him and just totally stopped him in his tracks."
The Golden Gloves version of a man in motion was a former high school football star at Dover (N.H.) High, who now works as a special education instructor at Newmarket (N.H.) Junior/Senior High School.
Clark, 25, established his jab early in the fight. From there he continually pressed Pineda, scoring with combos to the body and head.
"I just want to brawl," said Clark, a Barrington, N.H.
Pineda attempted to match the blistering pace set by Clark. But Pineda, 27, has been sick in recent weeks and his stamina wasn't where he would have liked it to be for a bout of this magnitude.
"It was a good, hard fight," said Pineda, 27, a Waltham resident with a 7-2 record. "He's a good fighter. I wasn't feeling my best, but I went out and gave it my best shot."
Pineda held his ground and tried to stand and throw with Clark, but he had a tough time landing clean punches.
"(Clark) did a really good job moving his head," said Murphy. "I made a vow to myself to have my boxers not get hit in the head. We call the head their computer. They have to take care of their computer and get it out of the way. He does a real good job at that. He fights smart. That shouldn't come as much of a surprise since he has a master's degree."
The only loss of Clark's amateur career came in the 2011 Greater Lowell/Central New England Golden Gloves Tournament. Although redemption isn't the driving force in his Golden Gloves return, he has worked hard at becoming the best boxer possible.
"I came here in 2011 and lost my second fight," said Clark. "I just stuck with boxing and I'm happy to be here in this position. It is an honor to me. Boxing is a hobby for me. I want to be a teacher, not a fighter. But I love to compete."
The stakes get higher with every win, and Clark is looking forward to moving on in the tournament.
"Things went great for me tonight," said Clark. "I stuck to the game plan me and Linda came up with for the fight and it worked great. Linda has really helped me get to this point.
"(Pineda) was a really tough kid. It takes two people to have a great fight, and my hat's off to him. This was a big win for me."
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