Johnson battled his way through the first half, leaving most of the kicking to halves partner Chanel Harris-Tavita and fullback Reece Walsh, who combined for six kicks, while Johnson had just five - mainly during the early exchanges of the game.
Johnson was also clearly struggling with his range of movement, missing four tackles and not running the ball at all during the opening 40 minutes.
The Warriors found themselves taking a surprise early lead on the night the Panthers would lift the minor premiership, only to fall apart in the lead up to halftime, with the Panthers taking a 22 points to 6 lead into the sheds.
The veteran halfback was seemingly hopeful of returning for the second half, however, a fitness test during the interval ruled him out of the remainder of the game.
At this stage, it's unclear as to the severity of the injury and whether Johnson will be able to return next week, or if the Warriors will be forced to call on Daejarn Asi for the final week of the season to partner Chanel Harris-Tavita in what will be his final game in the NRL before taking a break from the sport.
Given Friday's bench against the Panthers, Johnson has no obvious immediate replacement to play out the game, with Taniela Otukolo and Freddy Lussick likely to share five-eighth duties while Chanel Harris-Tavita moves to halfback.