 Complete the following phrase:  Robinson greatly improved in the 2016 outdoor season, setting the fastest time for an American that season with 49.10 seconds in April  over a second improvement on his 400 m hurdles personal record. He won the hurdles at the Big 12 Conference in 49.39 seconds, but withdrew from the NCAA qualifiers for undisclosed reasons. Working with coach Tonja Buford-Bailey, Robinson entered the 2016 United States Olympic Trials and improved further to 48.79 seconds to finish runner-up to former world champion Kerron Clement. He beat Olympic silver medalist Michael Tinsley in the process and gained a place on the United States Olympic team. At the 