Gaethje has fought better competition but also has lost for the most part to that better competition.
Starting before the Khabib loss, Geathje beat Ferguon, Cerrone, Edson Barboza, and James Vick after his back to back losses to Poirier and Eddie Alvarez. All those wins were finishes. The TKO against Ferguson was called at 3:39 of the 5th round.
For Oliveira, after his last loss (to Paul Felder), he has beat:
Ferguon, Kevin Lee, Jared Gordon, Nik Lentz, David Teymur, Jim Miller, Christos Glagos, and Clay Guida. All finishes except for against Ferguson. But it was only a 3 round fight, and pretty dominant. You can't say for sure he'd have gotten a submission or TKO quicker than Gaethje if it was 5 rounds, but I consider them equivalent victories since neither had him finished through 3.
If we ignore the bigger names Gaethje fought since he lost to them and toss the common victory, what impresses you more?
Cerrone, Barboza, Vick
or
Lee, Jared Gordon, Lentz, Teymur, Jim Miller, Glagos, and Guida
People want to dog on Oliveira's strength of victories, but Vick is the living embodiment of CTE and Cerrone has never shown up in a big fight. I will take the bigger pile of meh, lol.
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This is very wordy, but you tell Poirier he gets to choose cash or strap, but tell him there is no chance in hell he fights for the belt next if it is against Mr. Losing Record in the weight class. Like come on, people. Conor's only win at 155 is against Alvarez since he left Cage Warriors! If DP wants to fight him to chase money, have at it.
My order of preference for fighting for the belt is:
Poirier v Oliveira
Then Gaethje v Chandler for #1 contender fight.
If Poirier wants to go fight Conor for the money instead, he has earned it. If they go that route, flip a coin of who to bump up to fight Oliveira between the other two and have the leftover guy fight Dariush.
Frankly, Dana needs to get it through his fat tomato can head that Khabib is done and get the f***ing division going.