Dobengal

Dobengal (ドーベンガル Doobengaru) is a Mage of the currently strongest Guild in Fiore, Sabertooth and ranks within the top 10 Mages of the guild.

Dobengal is present with the rest of the Sabertooth members in Crocus during the Grand Magic Games, while Natsu is attacking their lodging, wanting to battle his Guild's Master. When Natsu reaches Jiemma, Jiemma calls on Dobengal to attack Natsu. He charges towards Natsu telling him that he won't let him reach his master and attacks Natsu, but Natsu dodges Dobengal's attack, and proceeds to defeat him in one punch, shocking the rest of his guild members. Stating Natsu to be as strong as one of the strongest in Sabertooth.

(Source: Fairy Tail Wiki)