1.) One way to do that is if you know your foe is going to be agresive let him come to you instead of you to him. You lost one round of your servitors hitting him by walking into the room instead of letting him come at you. When you are eating 33% damage in round one every round is precious.

2.)If you were not, wield an exotic weapon, you are not likely to be getting much melee damage in against a warrior anyway try to maximize your chance to parry.shield block.

3.) Everyone else has said it but some dam redux. In this fight you likely would have been fine with just proctection. It is a 25% dam redux which means you live 25% longer. you lasted 3 rounds in this fight so you likely would have made it to round 4. If you had waited in a room so your servitors wouldn't have to catch up (and happy enough they assist right away) you could have had 2 more rounds of them dealing damage, which would have doubled their damage likely (and a single wrath would likely do him in)

4.) use your familiar, the coyote actually does add a bit of damage and it can tank at least 3-6 rounds for you against a warrior even without the edges. Sit in the room and initiate combat with the enemy with the familiar. this will give you at least 1 extra round and often times 2-3 rounds before you get redirected on or have to release your familiar. so with the 2 suggestions above you got likely at least 3 extra rounds of servitors hitting the guy you want to kill. You likely had him gushing after 2 rounds so another 3 tips the scales in your favor substantially from a statistical stand point.

also keep in mind that by keeping the fight close people are less likely to run away before they die.