Okay, so today I finally got around to digging into that Mertens Tennis Score thing everyone keeps mentioning. Looked confusing as heck at first, but I sat my butt down and figured I’d wrestle with it until it made sense. Grabbed my laptop, a cold coffee, and just dove in headfirst.

Starting From Absolute Zero
Didn’t even know where to begin, honestly. Opened up a blank spreadsheet first—always my go-to when learning something new. Started scribbling down what I thought the method did: something about tracking points in a way that gives players a “score” for their form or something? Honestly felt like reading gibberish articles about it earlier.
Found this super old forum post explaining the core idea: you track sequences of points in a match. Like, not just who won, but how they won ’em. So I made two columns: one for Player A, one for Player B. Every time a point ended, I jotted down if it was won by an ace, a winner, unforced error, whatever.
- Typed “Ace – Player A” after a fake serve I imagined.
- Next point: “Unforced Error – Player B”. Filled maybe 20 rows like this just to test.
The “Oh Crap” Moment
Here’s where I got stuck bad. Articles kept talking about this “aggregated sequence value” nonsense. Tried calculating some made-up scores manually – took forever and felt messy. My spreadsheet looked like a toddler smashed the keyboard. Almost gave up right there, but remembered: keep it stupid simple first. Dropped the formulas and just color-coded cells instead.
Made three highlight colors:
- Green for strong wins (aces, winners)
- Yellow for normal points
- Red for weak losses (double faults, unforced errors)
Suddenly I could see patterns. Player A had a bunch of green early, then a streak of red. Visual click! Still didn’t know how to math it out, though.

Cheating Smarter, Not Harder
Said screw it and searched for a pre-made tennis point tracker app. Found this basic one where I could input points and it spit out totals. Fed it my pretend data – boom! The Mertens score popped up automatically. Turns out it weights those point types differently. Heavy on aces/errors, lighter on rallies. Watched the number jump after each “strong” point I added. Felt like unlocking a video game achievement.
Played with it like crazy:
- Added 5 aces in a row? Score ballooned.
- Dumped in 3 double faults? Plunged like a rock.
Finally got why people use it – shows momentum shifts brutally clear.
My Dumb Real-World Test
Decided to try it live during my buddy’s amateur match this afternoon. Sat courtside with my phone app open. Tapped furiously after every point:
- “FOREHAND WINNER – PLAYER 1” tap
- “UNFORCED ERROR – PLAYER 2” tap
Score shifted constantly. Player 1 was up big early, score super high. Then Player 2 clawed back with consistent shots – Mertens number actually dipped for Player 1 even when he was still ahead on games! Wild stuff. My buddy later asked why I kept cackling at my phone. Showed him the graph – total “aha!” face.

Took me half the day and a dead coffee to get it, but damn. Once you stop overcomplicating it and just track points honestly, the method’s kinda genius for spotting who’s actually playing well, not just scoring lucky. Totally adding this to my coaching tools now. Worth the grind.