St Kilda has named its 26-man extended squad ahead of Sunday's clash with Port Adelaide at the Adelaide Oval.

Veterans Jack Steele and Jimmy Webster have both been named on the field as they continue to complete fitness tests on knee and ankle injuries respectively, while Liam Stocker has been named in the extended squad after suffering a concussion against Geelong in Round 2.

Steele was a late out against the Tigers in Round 3 with a knee complaint, meaning rookie Tobie Travaglia was elevated to the starting 22 for his AFL debut and Angus Hastie was moved from emergency to the starting substitute.

Travaglia and Hastie have both been named on the extended bench, as well as Harry Boyd who last played in Round 1 and rookie Hugh Boxshall who has yet to feature for the Saints.

Liam O'Connell is the only confirmed out thus far for St Kilda after suffering a concussion against Richmond.

The game will be played at 3:20pm AEST on Sunday, and will be broadcast live on Channel 7, 7plus and Kayo.