From 2016 Guinard regularly played professional tournaments on the third-rate ITF Future Tour , where he rarely won matches at first. In 2017 he reached his first semi-final there in singles, while he won his first title in doubles. In the world rankings he was among the top 1000 at the end of the year. At the beginning of 2018 in his first Challenger main draw in Rennes , he was able to win two matches and reach the quarter-finals straight away. The rest of the year he played almost only futures and was victorious in three tournaments in singles and one in doubles. He made a leap in the ranking and was able to reach his previous career high with 370th place in October 2018.