Colt Knost and Tommy Armour III shot 70s Saturday morning to tie Paul Casey, Geoff Ogilvy and John Senden for the lead at 8 under after two rounds of the Shell Houston Open.

Fred Couples and Henrik Stenson were among five players at 7 under. Justin Leonard and 2006 champion Stuart Appleby were in the group of seven players two shots back.

Phil Mickelson missed the cut at 9-over par. Mickelson shot a 77 in the first round, then took two triple bogeys on Saturday on his way to a 76.

The third round was starting later Saturday afternoon. The tournament has been playing catch-up after high winds forced suspension of play Thursday.

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