Bean, who matched the course record Friday with a 9-under-par 63, is an 11-time winner on the PGA TOUR, but has yet to visit the winner's circle in almost three seasons on the elder circuit.
Only once in those three seasons has Bean held a piece of the 36-hole lead and that turned out poorly for the 53-year-old. At the 2004 Farmers Charity Classic, Bean shared the second-round lead with Bob Gilder, but fell ill on the driving range due to something he ate. Bean was taken to the hospital and was forced to withdraw.
Assuming he stays away from any bad chicken Saturday night, Bean knows what kind of opportunity he has on Sunday.
'The game is starting to be fun again,' said Bean. 'I'm hitting a lot of good shots. I need to just play a little better tomorrow. You put pressure on yourself to win. I was very patient out there today.'
Doyle, who won his second consecutive U.S. Senior Open title this summer, posted a 6-under-par 66. He is alone in second place at 9-under-par 135, which is one better than Tom Kite (68), R.W. Eaks (67) and Champions Tour rookie Chip Beck (69).
Bean began the second round with a four-shot lead and did nothing to hurt that margin early in round two. He birdied the first and seventh holes, but then battled a balky putter.
At the ninth, Bean's 2-foot par putt lipped out of the hole. He collected his second bogey in a row at 10 when he missed the green, then missed a 5-footer for par.
Bean wasted little time in making up the lost strokes. At the par-4 11th, Bean rolled in a 10-foot birdie putt to get back to 10 under par for the championship.
Bean, who uses a conventional putting technique on all putts outside 5 feet and a claw grip inside 5 feet, converted a pair of tricky 5-foot par putts at 13 and 14. He made routine pars the rest of the way until the par-5 closing hole at the Jones Course at Rock Barn Golf Club and Spa.
He found the fairway off the tee, then reached the putting surface with his second - barely. Bean left himself close to 100 feet for eagle, but lagged it inside 6 feet. Bean drained the birdie putt to move two shots clear of Doyle.
'I really played quite well except for two holes today,' acknowledged Bean. 'All in all, I didn't play much differently than yesterday, I just didn't make the putts.'
Doyle, who upstaged Tom Watson in Kansas this year for his fourth major title on the Champions Tour, birdied the fourth and fifth holes, but it wasn't until the back nine that he became a factor.
Doyle hit a hybrid club left of the target at nine, but the ball spun 3 feet from the hole. He converted that birdie putt, then rattled off back-to-back birdies from the 11th, including a 45-footer at the 12th.
At the par-3 15th, Doyle knocked his tee ball stiff. He kicked in the 2-footer there and had 11 feet for a birdie at the last. Doyle not only missed the putt, but ran his birdie try 4 feet past. He holed that putt to remain the closest pursuer.
'Good day today,' said Doyle. 'I want to be in the mix on the back nine Sunday. It all comes down to that. You hope if you're trailing they guy you're chasing notices you're there.'
Hajime Meshiai (67), two-time winner this season Brad Bryant (68) and Tom Purtzer (69) are knotted in sixth place at minus-7. Ron Streck (66), Joe Inman (68) and Dana Quigley (71) share ninth place at 6-under-par 138.