Deuce court, slice serve out wide. I admit it was very close. If it wasn't spot on the line, I probably missed it by half a tennis ball. Anyway, from my angle it looked good, so I started walking to pick up a ball and serve on the ad court. Half way through my leisure walk to retrieve the ball for the next point, he shouts "OUT!" At least 10 seconds have gone past since the ball in question touched the ground. Naturally, I stopped and went , didn't argue and walked back to the deuce court for a second serve. This is where I got mildly agitated: He offered me a first serve instead. Now, I'm fine if he called a line-clipper out on the spot, because he was there, and he had a better view of it. But I don't think it was right for him to: 1) Have doubts about the call himself, evident by the long pause. Then make a 50/50 choice. 2) No evidence of the spot, the court was not dusty and he didn't even walk to the spot in question. He just stood behind the baseline, thought about it, and shouted "OUT!" 3) Ace or fault, you can't just erase it because you weren't sure. What's to stop you from having a "do over" on anything that's close to the line? He exhibited some other gamesmanship too, but that's for another discussion. I'll just list them here: 1) Wasted a LOT of time between points 2) Excessively long change-overs (in my opinion) 3) Shadow/check swings/tosses on big points during his service games. That's gamesmanship in my book because he was trying to freeze me out on breakpoints. Curious to see who would have said something to the dude if they were in my shoes?