WEST Coast defender Mitch Brown's tough run of luck has continued, with the 27-year-old set to miss at least eight weeks after finger surgery.

But the news is more positive for recruit Lewis Jetta, who has avoided a serious calf injury and is on track for round one, while Chris Masten is six weeks away from returning from an ankle problem.

In just his second NAB Challenge game back after a knee reconstruction, Brown ruptured his tendon on the middle finger of his left hand against Gold Coast last Thursday.

The 195cm big man has undergone surgery that is likely to rule him out until at least round five or six.

Meanwhile, Jetta had been in good touch against the Suns in his second match for the club since his switch from the Sydney Swans when he hobbled off with a calf sprain just before half-time.

However, the electric 26-year-old was back jogging at a rehabilitation session on Monday and is aiming for a club debut against the Brisbane Lions in round one.

Masten, who badly hurt his ankle in an intra-club match last month, is progressing well and should return in about six weeks after an initial eight to 10-week prognosis.