Pokémon's Ash Ketchum is ambitious, loyal, stubborn, and creative as a trainer and a person. While adventuring, these traits help guide Ash whenever he encounters a problem. Whether he is foiling one of Team Rocket's schemes or battling against a Gym Leader, Ash relies on these characteristics to win. Most of the time, this is enough.

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Yet, some opponents Ash faces are simply too powerful. Whether they are using new skills, new Pokémon, or have more experience, Ash finds himself on the losing end when battling them. Ash's inexperience, lack of knowledge, or rash decisions ultimately lead him to defeat. While Ash often comes back to battle again, he learns some good lessons along the way.

10 Richie

Ash battles against Richie in "Friend and Foe Alike." Despite it being Ash's first tournament, it appears to be an even match. Richie takes out Ash's Squirtle, then Pikachu defeats Richie's Butterfree. Next, Richie sends out Charmander. Ash uses Charizard, who dominates the battle, ending it quickly. However, the problem lies in Ash choosing Charizard, a Pokémon he has not properly trained and is therefore unpredictable.

Richie chooses his Pikachu, Sparky, for his last Pokémon, and Charizard loses interest. Ash loses due to his Pokémon's refusal to battle, thus unintentionally forfeiting the tournament to Richie. This is a hard lesson for Ash to learn, and one that leads him to make better choices in future battles.

9 Lt. Surge

Anime Pikachu vs Raichu In Battle With Lt Surge Pokemon Anime

Ash challenges Lt. Surge to obtain the Thunder Badge in "Electric Shock Showdown." Lt. Surge believes Pokémon need to evolve right away to be strong, and faces off with Ash's Pikachu using Raichu. The battle begins and Pikachu is quickly overpowered by Raichu. Ash tries to switch Pokémon, but Pikachu refuses to swap and ends up hospitalized as a result. Ash's inability to call back Pikachu shows his empathetic side but also highlights his inexperience.

A more seasoned trainer may have changed Pokémon regardless of Pikachu's feelings, thus hurting Pikachu emotionally while protecting it physically. However, Ash does learn from this battle and ultimately returns with a different strategy, defeating Raichu and earning his badge.

8 Tobias

Tobias and Latios versus Ash

Ash battles Tobias in the semi-finals of the Sinnoh League in "The Semi-Final Frontier!" While Ash starts the battle feeling confident, the match quickly becomes one-sided. Tobias' Darkrai eliminates Ash's Pokémon one after another, knocking three out of the running before Ash finally puts a stop to it.

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However, Tobias' second Pokémon, Latios, picks up where Darkrai left off, defeating two more of Ash's Pokémon without breaking a sweat. With only one Pokémon left, Ash uses Pikachu. With his speed, endurance, and the help of his Iron Tail move, Pikachu manages to defeat Latios but is defeated in the process. Ash loses to Tobias, who has four Pokémon left. Ash gets an A+ for effort, but Tobias takes the well-deserved win.

7 Sabrina

sabrina in pokemon

Ash bites off more than he can chew when he challenges Sabrina in "Abra and the Psychic Showdown." Sabrina states that if Ash loses, he and his friends have to stay to be her friends and play with her. Despite the unsettling atmosphere and strange request, Ash agrees to the match. Sabrina then reveals her true self, a much older girl who controls the doll Ash spoke to. She declares a one-on-one match and chooses Abra. Ash attacks with Pikachu, but Abra's teleportation proves an effective way to dodge.

Abra then evolves into Kadabra. The match is over quickly when Kadabra uses confusion and Pikachu's attack turns on it. Kadabra finishes the match by using Psychic Attack to slam Pikachu repeatedly between the ceiling and the floor, and Ash is forced to forfeit to save his Pikachu. When Sabrina traps Ash, Misty, and Brock in her toy chest as a consequence, Ash realizes the grave mistake he made.

6 Brock

Onix vs Pikachu Pokemon Anime

Ash battles Brock, the Pewter City Gym leader, early in his journey. However, Brock is significantly more experienced and ends the match before it ever really begins. Ash's lack of understanding of his Pokémon's natural strengths and weaknesses proves his undoing as he challenges a gym leader specializing in rock-type Pokémon with his electric-type Pikachu. Brock chooses Onix, and it is all Pikachu can do to run away. Onix quickly catches Pikachu and uses its Bind attack to squeeze it into submission.

With no way to recall Pikachu, and thus no way to move forward, Ash is forced to forfeit the match to prevent any further harm to his Pokémon. Ash learns from this match, realizing that he can use water to his advantage, but his first match is a one-sided battle Ash will never forget.

5 Blaine

Blaine ready to battle Ash

Ash battles Blaine's Ninetales with Squirtle, keeping in mind a fire Pokémon's natural weakness. Despite Squirtle's water gun attack, Blaine's Ninetales quickly overpowers and defeats it. Ash then sends out Charizard, and Blaine counters with Rhydon. However, the battle never happens, as Charizard leaves the ring, thus being disqualified.

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Ash chooses Pikachu as his last Pokémon, finally defeating Blaine's Rhydon. However, when Blaine chooses Magmar, Pikachu is outmatched. Magmar's intense heat burns Pikachu throughout their battle, and ultimately Ash is forced to quit rather than risk Pikachu's health any further.

4 Whitney

Pokemon anime Miltank and Whitney

Whitney teaches Ash an important lesson: No matter how one-sided a battle may seem, it can be flipped in an instant. Ash seems to have the upper hand in this battle, quickly defeating Whitney's Nidorina with Cyndaquil. When Whitney's Clefairy mimics a Magikarp, Ash gets a second easy win. However, Whitney proves her capability as a gym leader by using Miltank, quickly defeating every one of Ash's Pokémon.

Ash uses his previous lessons learned to try to defeat Miltank, getting it wet and then electrocuting it, but learns that even a type advantage may not always be enough to secure a victory.

3 Samurai

Anime Ash vs Samurai Pokemon Anime

Samurai teaches Ash a hard lesson very early on in the series. Ash tries to battle with his Pidgeotto after using it against Weedle only moments before, resulting in his Pokémon being too exhausted to battle. Embarrassed, Ash chooses Metapod as his next Pokémon, defeating Pinsir by using Harden. However, when Samurai chooses a Metapod as well, the longest battle of their lives begins.

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Ash and Samurai continue commanding their Metapods to use Harden, the only thing they can do, and this goes on for hours, much to the embarrassment of all involved. When the battle is interrupted by a swarm of Beedrill, Ash is humiliated once again when he forgets to call back his Metapod, instead using his Pokédex to analyze the Beedrill. As a result, Metapod is taken by the swarm, and Ash's reputation as a trainer is badly tarnished.

2 AJ

Ash, Pikachu, and AJ in Pokémon.

After winning his first two badges, Ash's confidence is sky-high. However, this becomes his downfall when he challenges AJ, a trainer with 98 wins and 0 losses, in "The Path to the Pokémon League." Ash feels superior to AJ because he has badges while AJ doesn't, thus believing he is the better trainer and disregarding AJ's many wins. Ash battles AJ's Sandshrew with Pidgeotto and is quickly defeated when Sandshrew attacks Pidgeotto in the air.

Ash then uses Butterfree, but can't land an attack when Sandshrew digs under the ground. It emerges to tackle Butterfree and ends the one-sided battle in only minutes. Ash's confidence takes a hit, and he learns that while being confident is good, being overconfident can lead to defeat.

1 Roark

Roark vs Ash Pokemon

Ash battles Roark immediately after his rival, Paul, in "A Gruff Act to Follow." When Paul takes the win and obtains a badge, Ash is determined to do the same. However, Roark's Cranidos quickly defeats Ash's Aipom, and it takes Turtwig to finally defeat it. Ash's renewed hope for a win is short-lived when Roark uses Onix and immediately knocks out Turtwig.

Onix then defeats Pikachu, thus sealing Ash's fate. Not only has Ash lost, but his defeat happens in front of his rival. With a loss on his plate and the embarrassment of losing in front of Paul of all people, this is a loss that Ash will not soon forget.

NEXT: 10 Times Ash Met His Match (But Won Anyways)