Werner Mölders
On 5 June, Balthasar became an "ace-in-a-day", claiming two Lioré et Olivier LeO 45 medium bombers, a Potez 63 bomber a two M.S.406 fighters shot down. The next day, he claimed four further victories, three LeO 451s and a M.S.406, which brought his World War II tally to 21. For this achievement, on 14 June 1940, Balthasar was awarded the Knight's Cross of the Iron Cross (), becoming the second Luftwaffe fighter pilot after Werner Mölders, to be so decorated. With 23 aerial victories, Balthasar was the most successful German fighter pilot of the Battle of France.