Jenner was an all-rounder who was right-handed as both batsman and bowler. He was an underarm bowler but his pace is unknown. He kept wicket when not bowling, and is said to have been one of the "finest amateur wicket-keepers".
In the 1820s, Jenner did not wear gloves or pads while keeping wicket. These protections were gradually introduced in response to the development of roundarm bowling from 1827. Until then, the role of the wicket-keeper had been "offensive" rather than "defensive", in that he was primarily concerned with looking for stumping chances, but the increased pace of roundarm forced wicket-keepers to improve their ability to stop the ball, and so prevent byes. By 1836, the Kent wicket-keeper Ned Wenman was using gloves, but it is not known if Jenner himself adopted them in the latter part of his career.
Jenner was associated with Cambridge University, Kent, and Marylebone Cricket Club (MCC). He played for several predominantly amateur teams including the Gentlemen in the Gentlemen v Players series. He made 36 known appearances in important matches from 1825 to 1838. He scored 842 runs with a highest score of 75. He is credited with 75 wickets, including a best performance of seven wickets in an innings; he took five wickets in an innings on at least five occasions. As a wicket-keeper, he took 24 catches and made 17 stumpings.[2]