JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://cdnjs.cloudflare.com/ajax/libs/phaser/2.6.1/phaser.min.js"></script>

JavaScript

var game = new Phaser.Game(800, 600, Phaser.CANVAS, 'phaser-example', { preload: preload,create: create, update: update, render: render });

function preload() {
   game.load.image('circle', 'https://s13.postimg.org/xjhlzmiev/disc_png.png');
};

var player
var opponent
function create() { 
player=game.add.sprite(100,50,'circle')
game.physics.enable(player, Phaser.Physics.ARCADE);
player.body.velocity.y=800
opponent=game.add.sprite(200,200,'circle')
game.physics.enable(opponent, Phaser.Physics.ARCADE);
opponent.body.velocity.y=0
};

function update() {
game.physics.arcade.collide(player,opponent,collisionHandler,null,this);
};

function collisionHandler (obj1, obj2) {
console.log("collide")
    //game.stage.backgroundColor = '#992d2d';
};

function render() {
}