Olympic champion Mondo Duplantis broke his own world pole vault record yet again with an incredible 6.21 metre clearance in the last day of competition at the World Athletics Championships in Eugene, Oregon. The 22-year-old Swedish vaulter had already secured a gold medal when he set a championship record with a 6.06m leap. Once the bar was raised to 6.21m, he missed his first attempt, almost falling off the mat as he came down. His second try however was successful, and closed the world championships with a bang. The Tokyo gold medallist had raised the world record to 6.20m when he won the in…