Goku has always been Vegeta’s greatest rival since their very first encounter on the battlefield in Dragon Ball Z. Despite Vegeta often being on par with and even surpassing Goku in terms of raw power at times, Goku has always claimed to be the strongest fighter in the universe for the long haul.
However, while Goku is undoubtedly Vegeta’s greatest rival on the path to becoming the strongest, Kakarot does not truly represent the person Vegeta worries about the most. In reality, the most significant obstacle for Vegeta throughout the entire Dragon Ball Z series has always been Krillin.
While Vegeta has faced numerous defeats and has lost to much stronger foes, Krillin has proven to be the one who often remains a critical factor in Vegeta’s survival.

Krillin has defeated Vegeta multiple times in their first encounters
Specifically during the Saiyan Saga, Krillin was a constant threat to Vegeta and was consistently undermined during the final battle. Although Goku received the lion’s share of credit (and the spotlight), it cannot be denied that he couldn’t have achieved his goals without the contributions of his comrades, including Krillin.
While Gohan demonstrated his potential to fight Vegeta for a time, Krillin’s contributions were crucial in distracting the Saiyan Prince at the most critical moments. To achieve that objective, Krillin had several successes.
The very first time Krillin inflicted damage on Vegeta’s heart was when Vegeta transformed into a Great Ape. While the characters that appeared in the future would be shown to be strong enough to surpass the Destructo Disk, at that moment in the Saiyan Saga, Krillin’s Destructo Disk was a formidable attack capable of slicing through any opponent if they were hit by it.
This allowed Krillin to have an important role throughout the Namek Saga, even as he was becoming one of the most beloved members of the Z Fighters. In the Saiyan Saga, Krillin’s Destructo Disk was able to cause real harm to Vegeta, and the truth is that it nearly severed his tail while he was in his Oozaru form.
Unlike most other energy attacks, Vegeta had to rely on his own strength to withstand the attack, as Vegeta didn’t want to show any weakness regarding the devastating power of the Destructo Disk.

Krillin had been a constant thorn in Vegeta’s side throughout the series, but the most notable moment came during the final battle. Initially, it was through Goku’s Spirit Bomb. With Goku severely injured and unable to use the Spirit Bomb himself, it was handed to Krillin to launch the finishing blow using the technique he usually employed from King Kai. After gathering an overwhelming amount of energy, Goku instructed Krillin to execute the attack, which could only be initiated with a minimum amount of energy from Goku.
If Yajirobe hadn’t shouted at Krillin to “throw it already” while Krillin was holding the Spirit Bomb, Vegeta might have lost his guard and could have been killed right then. The only thing that remained in memory was Gohan striking Vegeta with it and Vegeta still surviving, but at that moment, he had at least prepared a spiritual defense for the attack. While if hit by the Spirit Bomb without any prior warning, the damage would have been far greater. Of course, this wouldn’t be the last time Vegeta faced a severe threat from Krillin’s hands.

One of the most iconic moments of Dragon Ball Z occurred at the end of the battle when Vegeta fled the battlefield after Oozaru Gohan fell to the ground. With Vegeta completely defenseless, Krillin found a way to launch a finishing blow with Yajirobe’s sword. Even King Kai acknowledged that Krillin was likely to kill Vegeta, but Goku begged him to hold off at the last moment.
Krillin continues to be a divine warning sign for Vegeta throughout Dragon Ball Z
The Saiyan Saga witnessed Krillin as the most significant threat to Vegeta in Dragon Ball Z. Krillin’s power level may have been modest, but his unwavering loyalty made him a crucial nemesis for Vegeta’s ultimate strength.
During the Frieza Saga, Vegeta ultimately died at Frieza’s hands, but he had to confront a series of hurdles before that demise. While Vegeta fell to the ground under the attacks of other adversaries like Zarbon and Recoome, the most memorable moment of impending death surely came from no one other than Krillin. In the early stages of the battle against Frieza, the Z Fighters were already struggling to cope with Frieza’s growing power and transformations.

Hoping to become a Super Saiyan through Zenkai, Vegeta ordered Krillin to try to kill him so that Dende could heal him and make him stronger after the traumatic experience. Initially resisting, Krillin was met with another transformation that left him horrified—Vegeta was mortally wounded after a blow from Frieza, leading to his death.
In reality, Dende had even begun to heal Vegeta at the start, a move that would prove fatal. Despite Vegeta’s demise due to Krillin’s energy attack, it was evident that Vegeta’s request would not change the reality that Krillin ultimately killed the Saiyan Prince himself.
This wouldn’t be the last time, either. In the Cell Saga, Krillin played a crucial role alongside Vegeta. While Goku was recovering from the heart virus and training in the Hyperbolic Time Chamber, Krillin and Vegeta had to fight against Androids and Cell alongside Trunks, Piccolo, and Tien.
However, Krillin inadvertently caused Vegeta’s death during one of the most chaotic moments. After Cell absorbed Android 17, he transformed into an incredibly powerful monster, capable of overpowering a Super Saiyan. Fortunately, Vegeta managed to surpass a regular Super Saiyan to become Super Vegeta.
With his new Super Saiyan form, Vegeta was ready to dominate Cell, even after Cell absorbed Android 17. However, to completely achieve that, Cell needed to absorb Android 18. Due to his overwhelming pride, Vegeta decided to let Cell absorb this Android to challenge himself against a stronger opponent.
Krillin certainly had the power to prevent Cell from reaching that level of strength by destroying Android 18, which would protect Vegeta and humanity. However, in a moment of weakness, Krillin chose to spare her life, allowing Android 18 to survive, ultimately giving Cell the opportunity to absorb her, leading to one of the most intense battles Vegeta faced throughout the series against Perfect Cell.
Source: CBR