Settling a Not-So-Old Score! (Japanese: 決戦！ポッチャマＶＳポッタイシ！！ Deciding Match! Piplup VS Prinpulp!!) is the 27th episode of Pokémon: Diamond & Pearl.
Dawn has thought of something - she reaches for her pocket and throws her Poffin. This causes Pachirsu to gain its attention and jumps to eat that Poffin. Pachirisu uses Discharge to dazzle the audience, then Sweet Kiss and it bashes the hearts to multiply them. This ends their performance. After some performances, it is Jessilina (aka Jessie)'s turn, so she sends Seviper. Dawn is feeling sad, as they could have practiced more. Kenny is appeased, as she showed him she got herself in order. Still, this Jessilina is quite something, as she seems quite powerful, according to Kenny. Dawn does not know why is Kenny into Contests, but Kenny tells her she never saw him in that expertise.
On Jessie's orders, Seviper wraps her. The audience are amazed, so Kenny tells Dawn he will make that lady look bad. Kenny sends Alakazam, who uses Light Screen to make a box, then Shadow Ball to crush it and teleports away to safety. Alakazam uses Hidden Power to spin the balls and levitates up. The audience are impressed, including Dawn. Later, Dawn is scared, so Ash and Brock give her confidence - Pachirisu made a better performance in the end. The screen displays the next Coordinators - among them are Jessie, Dawn and Kenny. Still, Dawn will have to fight Jessie in next round. Team Rocket are still happy Jessie passed this round.
Ash and Brock leave to get back to the seats. Dawn expects a fight with Kenny and he admits she became more experienced, though he still aims for his first ribbon. The battle starts - Dawn sends Piplup and Jessie her Dustox. Dustox starts with Whirlwind, though Piplup spins itself to evade. Piplup charges for pecking, so Dustox uses Poison Sting, though Piplup got a bit injured, as it evaded most of it. Dustox uses Psybeam, but misses. Dustox uses Poison Sting, but still misses. It uses again, though Piplup uses Bide to hurt Dustox. Dustox uses another Poison Sting, so Piplup charges for pecking. Piplup dodges and defeats Dustox. Jessie is nervous and wants to make a plan, but Meowth reminds her she spent all the money for make-up.
After some fights, Kenny and Dawn still remain. Dawn sends Piplup and Kenny his Prinplup. Piplup and Prinplup use BubbleBeam on one another - the collision causes glitter to be spread all over. Piplup charges to peck, but gets stopped and thrown away by Metal Claw. Prinplup spins and uses Drill Peck, though Piplup uses Bide to collect damage and hit Prinplp by it. Prinplup uses Metal Claw, but Piplup jumps over it and uses Whirlpool to engulf Prinplup by it. Still, Pirplup uses BubbleBeam to cleanse itself from it. Prinplup uses Mist to hide itself. Prinplup jumps and uses Drill Peck and Piplup uses Whirlpool, but it gets into it.
Piplup uses Peck, though Prinplup goes on the Whirlpool and uses Metal Claw to attack each other. Piplup and Prinplup use BubbleBeam on each other to cleans Whirlpool. Time ran out and the winner, who lost less points is - Dawn! Kenny is a bit disappointed, but knows he will run into Dawn once more. Dawn gets her first ribbon. Dawn contacts her mom and shows her first ribbon she won. Mom tells her to stay focused, as she needs more ribbons to get to Grand Festival and advises her to keep her team together. Dawn tells Ash he should next go to Eterna City's Gym. Kenny tells their paths will cross again and tells goodbye to Dawn, calling her Dee-Dee. Ash wants to know why does he call her Dee-Dee, but Dawn does not want to explain this one bit.
- Music from Lucario and the Mystery of Mew and a reduced cut of Ready Go! are used as background music.
- Professor Oak's Pokémon lecture: James's Carnivine
- Pokémon senryū: マスキッパ きょうもはらぺこ すきっぱら Masukippa, kyō mo hara peko, sukippara "Muskippa is also starving today: empty stomach."
- Marian mentions that Kenny's Alakazam's appeal is like watching a magic show, a reference to the Pokémon's name origin.
- Team Rocket doesn't blast off or recite their motto in this episode.
After Dawn's win against Jessie, Marian says that Dawn and Piplup are off to the final round, but Dawn vs. Jessie was a first round match. Piplup is later seen defeating a Bagon, and then fighting against Kenny and Prinplup in the final round.