WEST Coast midfielder Elliot Yeo is set for his third stint on the sidelines this season after scans revealed a hip issue that will keep him out for up to a month.

It's another blow for the depleted Eagles, coming just as they were preparing to welcome back premiership pair Jamie Cripps and Shannon Hurn for Sunday's clash against St Kilda at Optus Stadium.

Yeo, who has already been sidelined because of calf and groin injuries this season, experienced tightness late in the Eagles' disastrous 171-point loss to Sydney at the SCG.

Subsequent scans revealed irritation around his hip flexor, with the club confirming on Tuesday that the premiership star would miss at least the next three matches.

"He's struggling to get moving at the start of this week and we'll just need to let that settle down and then build through the rehabilitation for that," Eagles head of health Mark Finucane said.

Yeo's latest blow continues an extended run of frustrating setbacks for the dual club champion, who missed the opening three rounds this season with a calf injury.

The 29-year-old then experienced soreness against Geelong in round five after moving into the midfield, with scans revealing an adductor muscle injury that wiped out his next five weeks.

Yeo had made a strong return to the midfield over the past month but will now join an injured brigade that sits at 21 players this week after fresh injuries to Samo Petrevski-Seton (quad) and Jack Williams (ankle).

Scans cleared Williams of structural damage and the young forward will push to play this week as the Eagles prepare to pick a squad to face the Saints from between 25 and 27 fit players.

The Eagles expect relief through premiership forward Cripps (ankle) and veteran defender Hurn (hamstring). Jeremy McGovern (hamstring) will be unavailable after a minor setback.  

"We've taken an extra week than we might have otherwise to give him (Hurn) a really good build into this week's game," Finucane said.

"He's just got to get through training this week to be available.

"Jamie has done an outstanding job after his ankle fracture and has done a mountain of work and has integrated really comfortably into his football work and contact.

"If he has a good week at training this week, we hope to see him on the weekend."