The Hornets (5-7-4, 3-3-2 Big Sky) lost just once through their first six conference games but dropped both games at home this weekend. The Bengals (9-5-1, 4-2-1) won for the fourth time in their last five outings.
Kellogg put the Hornets up, 1-0, in the 20th minute with a header near the far post on a corner kick, but the lead would be short-lived.
Idaho State's Amanda Ellsworth scored on a loose ball in the box off a deflected shot in the 24th minute and then tallied the game-winner on a penalty kick in the 35th minute.
The Hornets had a big 8-1 edge on corner kicks (including 6-0 in the first half) but couldn't convert on any additional chances. Overall in the game, the Hornets had a 13-6 advantage on shots but Idaho State keeper Sheridan Hapsic made seven saves after allowing the early goal.
Sacramento State keeper made two saves while allowing both goals.
With the loss, the Hornets will have an uphill climb to get into the Big Sky Tournament. Portland State currently leads the conference with a 5-2-1 league record, but four teams (Northern Colorado, Idaho State, Montana and Weber State) are close behind with four conference wins. The Hornets, with a 3-2-2 conference mark, will need to win their Big Sky finale at Portland State next weekend and watch some of the teams ahead of them lose in order to move up in the standings. The Hornets are currently tied for sixth with 11 points (three for a win, one for a draw) and only the top four teams advance to the Big Sky Tournament.