Messenger photo by Eric Pratt: Terry Cook hits a tee shot during the quarterfinals of the IGA Senior Match Play Championships on Thursday at the Fort Dodge Country Club. Cook, from Norwalk, is the two-time defending Fort Dodge Amateur senior division champion.

There are four players remaining in both brackets at the 20th annual Iowa Golf Association Senior Match Play Championships, being held at the Fort Dodge Country Club.

Top-seeded Jay Gregory of Lineville held suit with a pair of victories on Thursday in the Senior competition. Gregory defeated Bob Brummel of Orange City, 4 and 2, and Brian Persson of Elk Run Heights, 2 and 1, to advance.

Ottumwa’s Jeff Collett, seeded fourth, will take on Gregory in the semifinals. Collett ousted Ankeny’s Jay Slings in 19 holes, then bounced Terry Cook of Norwalk — the two-time defending senior Fort Dodge Amateur champion — 5 and 4.

Second-seeded Joe Palmer of Norwalk and No. 14 Ron Peterson of Urbandale comprise the other Senior semifinal. Palmer pulled through in extra time by edging Troy Underhill of Legrand in 20 holes and Jon Brown of Adel in 19. Peterson eliminated Robert Dickerman of Marion, 3 and 2, followed by a 4 and 3 upset of sixth-seeded Chris Kramer (West Des Moines).

Gowrie’s Tom Schill, seeded second, has reached the semifinals in the Super Senior competition. Schill clipped Mason City’s Joel Yunek — a Lake City High School graduate — 1-up, then dropped fellow Gowrie resident Ned Palmer, 2-up, to stay alive.

Schill will take on David Studer of West Des Moines, the No. 6 seed, on Friday morning for a spot in the finals. Studer defeated Randy Studer of West Des Moines, 5 and 3, and Ankeny’s Tim Taylor, 5 and 4.

On the other side of the bracket, top-seeded Tom Norton of Muscatine and No. 5 seed Steve Kahler of Marion have reached the final four. Norton ousted Fort Dodge’s Dave Sergeant, 4 and 3, then bounced Pat Ryan of Marshalltown, 3 and 1.

Kahler clipped Mike McDonald of Ankeny, 1-up, before eliminating Carroll’s Jim Madsen, 2-up.

Gregory and Collett will open Friday morning action at 7:30 a.m., with Palmer vs. Peterson, Norton vs. Kahler and Schill vs. Studer to follow in eight-minute increments. The championship round will take place after completion of the semifinals.