"Clearly, this was deliberate to hurt him, and you succeeded," Weld County District Judge Marcelo Kopcow told Cozad as he announced the sentence.
"The goal is to not ruin your life," Kopcow said. "I would like you to succeed in your life."
Prosecutors said Cozad ambushed starting punter Rafael Mendoza on the night of Sept. 11, 2006. Mendoza was left with a deep gash in his kicking leg but later returned to the team.
Cozad was convicted in August of second-degree assault but acquitted of the more serious charge of attempted first-degree murder.
Cozad, 22, of Wheatland, Wyo., could have faced up to 16 years in prison on the assault conviction.
Mendoza testified he could not see who attacked him in the dimly lighted parking lot. The assailant was dressed in black from head to toe and had a hood cinched up so only the eyes were visible.
Defense attorney Joseph "Andy" Gavaldon had argued it was another university student who stabbed Mendoza, not Cozad.
Before Cozad was sentenced, prosecutors called four people Tuesday to make statements, including Mendoza and his mother, Florence.
Rafael Mendoza said he was convinced Cozad wanted to kill him.
"Even though he wasn't convicted of it, his intentions were clear," Mendoza said, fighting tears. "I'll never forget that. I've spend long nights since then waking up in a cold sweat, having nightmares, thinking I was going through that again."
Florence Mendoza asked Kopcow to give Cozad the maximum sentence.
"No matter how much time you give Mitch, it won't be enough," she said. "I don't believe he'll ever change. I don't know him as well as I thought. I'm suggesting you give him as much time as possible. I've been in fear way too long."