One Piece Chapter 52, page 19: OATH

As the smoke clears, Krieg's men realize Mihawk has already vanished. "GONE ALREADY..." they mutter in disbelief. Luffy yells to Usopp, Johnny, and Yosaku on their boat, "USOPP! GO ON AHEAD! ALRIGHT! ZORO AND I'LL DEFINITELY BRING BACK NAMI! SO YOU MAKE SURE TO GET US A COOK!". Usopp and the bounty hunters set sail to pursue Nami, leaving Luffy behind at the Baratie.