sportsnut13....I had something similar to what you had. I had a small pike on reeling him in when all of a sudden my buddy said he since something flash under the pike. He did alright, it was a muskie app 20 lbs. After grabbing hold of it he seemed like he just played with it, carried it away for a few seconds then let it go. I reeled in a pike with teeth and scrap marks on him.
Side note....just for interest sake, anyone that catches a muskie and are intending on releasing it, which would be nice, if you take the measurement there's a simple rule to get you the app weight. A 28 inch muskie usually is 5 lbs. Add a pound for every inch up, a 10 pounder would be 33 inches, a 15 pounder would be 38 inches etc. If anyone who has caught a muskie knows the weight and length maybe they could back this up. Last weekend my brother had called me as they were bass fishing and they had caught a muskie. The fish was bleeding profusely so he called to ask if there was any sense putting him back. They had measured him at 39 inches, so I had said he's in around 16 pounds. His gill plate was destroyed so they kept it and weighted it when they got back....16 pounds 3 ounces....so the rule proved itself again.