SLIPPERY ROCK — Bailey Mertens’ junior season was spent in a strange and frustrating football purgatory.

Each week, Mertens thought he would be able to get back on the field as the quarterback of the Slippery Rock High football team only to find out he had to wait another week.

And another.

And another.

“Every day (the doctor) would test me,” Mertens said. “And then say, ‘We need another week.’”

Mertens’ odyssey began in the waning days of September in the week leading up to a big matchup with region rival Hickory.

During a tackling drill, Mertens took a helmet to the right knee and crumpled to the turf.

Mertens was fortunate, however — relatively speaking. There was no damage to his ACL, but his MCL was shredded.

“We had a kid tear his ACL last year, and it seems like all our girls basketball players tear their ACLs,” Mertens said. “So, I definitely felt fortunate. The man upstairs was definitely looking out for me.”

Physical therapy was grueling, but Mertens hoped the injury would only set him back a few weeks.

It turned out to be for the season.

“It was the hardest thing,” Mertens said. “It makes you totally regret maybe taking a play off at practice. You just don’t know what to do. I only play football and I’ve played since I was 7. Football is my life. It’s one of the hardest things I’ll ever have to go through in my life.”

Mertens, now a senior, is looking at that lost season as a good thing as he enters a new beginning with the Rockets in 2016.

Slippery Rock has a new coach in Larry Wendereusz, who is bringing a spread offense with him.

Mertens, a runner in the Rockets’ option offense first and passer a distant second, is getting the chance to show off his passing skills.

And he couldn’t be more excited.

“Can’t wait. I cannot wait,” Mertens said. “I got questions all the time in the past about how much are you going to throw the ball,” Mertens said. “In the past I’d say not that much, we run the option. This year, we’re going to spread things out and teams aren’t going to know what we’re going to be doing. I’m so excited.”

Mertens spent the summer throwing and throwing and throwing with assistant coach Eli Christy. He also was a fixture in the weight room, packing 20 pounds of muscle onto his 6-foot-3 frame.

“I’m definitely a lot stronger this year,” he said.

He also participated in a slew of 7-on-7 drills with the Rockets against schools like Seneca Vally, Cardinal Wuerl North Catholic and Butler.

Learning the terminology and signals from the sideline have been the biggest chores so far for Mertens.

“The hardest part is seeing the signals,” Mertens said, smiling. “Some of the formations are only a couple of fingers different. But when you can run two plays in 30 seconds, that can put a lot of pressure on the defense.”

Wendereusz has liked what he has seen so far from his quarterback.

Wendereusz said he has already seen Mertens’ evolution in the offense.

“When you talk about growth with him, from the very day we started to throw the ball until now, it’s a good thing to be able to see him grow as a thrower and not just a runner.”