Bob Roper was the main bowler for Penylan Baseball Club and was capped twice for Wales in 1933 and 1934.

Roper played his first match for Wales against England at the Police Athletic Ground in Stanley. Roper was the opening bowler for Wales and bowled eight English batsment out for 40. When batting, however, he was bowled for 0 in the first innings and caught for 0 in the second innings.

In his second international for Wales against England, which was played in Cardiff in 1934, Roper was again the opening bowler and got four English batsmen out. Again, he was caught for a duck when batting in the first innings and scored four before being bowled out in the second innings. Nevertheless, Wales went on to win the match.

In the 1950s, Roper helped to form Llanishen Wanderers and trained a young man named Richie Morgan who later played for and managed Cardiff City Football Club.