"It's the first time I've ever had a game like this," Mertz said. "I couldn't believe how open I was and that was because of our transition game."
In the third quarter Mertz outscored Smithsburg by himself, 16-15. He had five two-pointers and a pair of 3s as he was constantly spotted bolting down the floor in transition and being found by Miner or Jamel Smith (six assists).
His 12-point burst, which lasted four minutes, catapulted the Rebels (15-5, 11-5) a 25-point lead with 2:49 left.
"We certainly went with the hot hand," coach Bob Starkey said of Mertz and his 14 of 22 shooting performance.
Smithsburg (13-8, 10-8) had beaten South in double overtime on Jan. 24 and the Rebels were ready to extract revenge once they got on the floor after a 10-day delay in activity.
"We notice their talk after they beat us and that kind of hurt our ego," Starkey said. "This was a crucial test for us. I think we will be hard to handle the rest of the way."
With the help of its enthusiastic student body, Smithsburg came out blazing at the tip to take control of the early tempo.
The Leopards bolted to an early 10-2 behind the whirlwind efforts of Corey Brown, who opened with three quick baskets.
However, South got its composure behind Miner and eventually took a 17-16 after the first eight minutes on a bucket by - you guessed it - Mertz.
Miner had 15 points and seven rebounds at the break and hit for 10 points in the second period.
South did a hot potato act with the basketball in the final period with 11 turnovers that kept Smithsburg alive with a 28-point quarter.
"We had a bad start and a bad finish," Starkey said. "But we're a calculated fury. Our energy is not contained."
Smith was a critical factor at the charity stripe for the Rebels as he connected on 13 of 14 toward his 18 points.
For the Leopards, it was their fourth straight loss, which left coach Eric Gerber perplexed.
"We came out strong and with lots of energy," Gerber said. "We just did not sustain it. Maybe it was due to the layoff, I'd like to think so. But at this point we just aren't playing well."
Brown led Smithsburg with 20 points which included several outstanding maneuvers around the basket. David Gouff added 18, including 12 in the second half. Brown also had 12 rebounds.
Due likely in part to recent activity, each team was guilty of 26 turnovers.