Skelly injured his shoulder fielding last month and the worst was confirmed this week with the spinner undergoing surgery.

It's another big loss as the Blues chase back-to-back premierships.

Skelly is the club's leading wicket-taker with 20 dismissals at an average of 16 this season.

With their leading runscorer Blake Harper already ruled out after a freak farming accident, South Wagga's stranglehold on the competition has lost some grip.

However captain Joel Robinson believes there is still plenty of talent available.

"It's disappointing for him to not be able to finish off the season, but from a club's point of view we wish him all the best and as far as our team goes moving forward I'm confident we've got enough depth to be able to cover both of our losses," Robinson said.

The Blues will be put to the test taking on St Michaels in the top of the table clash.

After a tie with Wagga RSL last week, Robinson is looking for a better performance at Geoff Lawson Oval, especially with the bat.

"We have to make sure we put our best foot forward this week, we obviously want to come away with the win to put us onto the right step going into the finals," he said.

Alex Jones comes back into the side in what will just be the second meeting between the two clubs.

South Wagga scored a eight-wicket victory in round third before their Twenty20 was abandoned due to hot weather leading into Christmas.

Skelly snared four wickets on that occasion.

The Saints are coming off their first win since December after easily accounting for Kooringal Colts.

They sit seven points adrift of the Blues, meaning they need an outright win to take the minor premiership but are just two points clear of Wagga City.

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