Devon Smith will miss Thursday night's Qualifying Final against Adelaide with knee soreness.

Giants coach Leon Cameron revealed the 24-year-old won't line up on Thursday night, after the forward didn't arrive with his teammates in Adelaide on Wednesday afternoon.

Smith struggled for form in recent weeks after battling the knee injury in the second half of the season.

However, veteran Steve Johnson has made the trip to South Australia despite his own issues with form.

Johnson has also been dealing with a knee problem – one that requires weekly draining and restricts his ability to train – and had just eight touches in the Giants' loss to Geelong in Round 23.

The three-time premiership Cat has already announced he'll retire at the season's end.

The Giants' three emergencies from Round 23 – Matt de Boer, Tim Taranto and Harry Himmelberg – have all made the trip, as well as first-year player Harry Perryman, who last played in Round 19.

The Giants will train at Adelaide Oval on Wednesday afternoon ahead of Thursday night's final.