McClellan (3-1) allowed just four hits and struck out seven in 6 2/3 innings.
The second hit McClellan allowed was a Rashad Albert home run in the second inning, but the Suns (29-24) retaliated with two in the bottom of the inning for a lead they would not relinquish.
Tony Peters and Josh Phelps hit back-to-back singles against Hickory starter Marty Weymouth (0-2) with one out to put runners on first and second. A Cesar Izturis ground ball forced Phelps at second, but moved Peters to third before Mike Young singled to tie the score and move Izturis to second. Chad Durham then booted Jesse Zepeda's ground ball, allowing Izturis to cross the plate with the go-ahead run.
"(Those runs) just loosened everything up," said McClellan. "You can relax and throw your game. You can go right at them when you have the lead."
Phelps, who had been struggling at the plate, widened the gap with his second home run of the season in the fourth over the centerfield wall.
"I've been working on my mechanics at the plate," said Phelps. "It was nice to get a couple of base hits, but I have to keep working on it. Tomorrow's another game."
Bobby Cripps unloaded his 12th homer of the year in the eighth for the 5-1 lead, while Brian Bowles and Jaron Seabury pitched the final two and a third innings without allowing a hit.
Hickory (17-36) mounted a threat in the seventh against McClellan, but Bowles came on with two outs, and ended the threat with just one pitch.
Suns pitchers have allowed just three runs and seven hits in the first two games of the series, while striking out 18.