Kronfeld (36), the University A assistant coach, sat on the bench for the injury-plagued University A team against Green Island at Miller Park.
''We've had a lot of injuries and Josh sat on the bench for us as cover,'' University A coach John Leslie said.
Kronfeld was not expecting to get on the field.
''But he started jumping around and I let him loose on the field with 10 minutes to go,'' Leslie said.
''Josh was good for 10 minutes, but I wouldn't want him on for 11 minutes. That would be too much.''
Kronfeld began his premier career with the University club in the early 1990s and his last game of club rugby in Dunedin was for Alhambra-Union in 2000.
Will he start next week?
''Definitely not,'' Leslie said.
''Josh is adamant that it's not a comeback, just a fill-in. But the boys enjoyed playing with him.''
Kronfeld played 69 games for Otago between 1992 and 2000, and 42 games for the Highlanders between 1996 and 2000.
He then went overseas and played another 39 first-class games for the Leicester Tigers between 2001 and 2003.
Kronfeld was in Christchurch yesterday and could not be contacted.
For the record, University A beat Green Island 28-5.
