A stocky player, who was known for his robust running and sharp shooting, 'Jolly Jack' earned his first cap for England on 6 November 1949, where he scored on his international debut, from the outside-left position in a 9–2 victory over Northern Ireland at Maine Road.
During his Poppies career Froggatt scored three hat-tricks, the first in the 6-4 thriller against Spalding United in the 1st Qualifying round of the FA Cup, in October 1958.
His second hat-trick was scored in April 1959 in the Southern League North West Division against Kidderminster Harriers as the Poppies ran out 4-3 victors at Rockingham Road during their promotion season.
1,800 turned out to see Pompey race into a 4–0 lead after just 35 minutes, before goals from Dennis Randall, Froggatt and George Armour made the score more respectable.
For 22 years, he kept the Manor House in Cosham, The Milton Arms near Fratton Park and a hotel in Partridge Green, West Sussex.