Forum:Nitro Warrior's second effect

I have a question about Nitro Warrior's second effect. Let me give an example: I have Nitro Warrior on the field, and my opponent only has a Pyramid Turtle. I attack the Pyramid Turtle with my Nitro Warrior, and my opponent special summons Ryu Kokki in defense mode with pyramid Turtle's effect. Can I use Nitro Warrior's effect to switch Ryu Kokki to attack mode and attack it with Nitro Warrior?