STOCKTON, Calif. -

The Reading Royals will have to wait at least one more night to clinch the Kelly Cup championship.

The Stockton Thunder prevented a sweep by defeating the Royals 4-3 Friday night in Stockton, Calif.

The Royals lead the best of seven series three games to one.

Game five is in Stockton tonight. The puck will drop 10:30 eastern time.

If the Royals fail to clinch tonight, the series will return to Reading for game six on Tuesday.