* Australian tied with Tringale after 65
* McIlroy also has a 65 to go three under (Adds details, quotes)
By Larry Fine
PARAMUS, New Jersey, Aug 22 (Reuters) - Adam Scott used a run of four successive birdies on Friday to vault into a share of the halfway lead at The Barclays, and Rory McIlroy joined the fray at the opener of the four-event FedExCup playoffs.
Scott, the Australian world number two, caught fire from the par-four fifth hole to post a 31 on the front nine and added two more birdies including a nice finishing touch at 18 to complete a 65 for eight-under 134 along with American Cameron Tringale.
Scott was hitting the ball like a dream from tee to green, and reckoned he might have broken 60 if he had taken advantage of the par-fives and cashed in with his putter on a host of other scoring opportunities.
"Always hard to put numbers on it but six, seven," Scott told reporters when asked how much better his score could have been.
"I played the par-fives one-over today. So I could find four there for you, and missed so many 10-footers it felt like."
Asked if a 59 might have been possible for him, Scott said: "Well, ifs and buts, but I played well enough if I had it really going on the green today to do that for sure."
Tringale, who last week disqualified himself from the PGA Championship for signing an incorrect scorecard, shot a 68 to share a one-stroke lead with Scott on a jammed pack leaderboard.
World number one McIlroy, on a blazing three-tournament winning streak that included major triumphs in the British Open and PGA Championship, shrugged off an opening 74 with a sizzling six-under 65 to move up to three under par for the tournament.
The Northern Irishman, who took some time off from practicing after his brilliant run, went back to work after his poor round and got right back on track.
"I know how well I'm playing and how comfortable I am with my game, so even to miss a cut feeling like that would have felt really bad," said McIlroy. "I put a little extra effort in yesterday and this morning and made sure I was ready to go."
One stroke behind the co-leaders were Jim Furyk (69) and fellow Americans Brendon Todd (69) and Kevin Chappell (67) on 135, one shot better than a group of six that included last year's FedExCup champion Henrik Stenson of Sweden and Australian Jason Day, who both fired 64s.
Also at six-under-par 136 were South African Ernie Els (68), Scotsman Russell Knox (69), Kevin Na (66) and Bo Van Pelt (71), the overnight leader.
Others struggled despite softened conditions from overnight rain on the A.W. Tillinghast layout.
Three-time winner this year Jimmy Walker struck a spectator in the head with an approach shot, and five-times major champion Phil Mickelson hit his tee shot on the short par-four fifth hole onto a hospitality dining deck and played on from there.
Mickelson went on to bogey the hole and shot a 72 but made the cut right on the number, while Walker posted a 74 to miss it by two.
The cut for the elite field was set at one-over-par 143, with 79 players carrying on to Saturday's third round at tree-lined Ridgewood Country Club.
The top 100 players on the FedExCup points list after the tournament will qualify for next week's Deutsche Bank Championship in Boston.
Among those missing the cut on an overcast but dry day, were European Ryder Cup veteran Ian Poulter (72) and 2012 FedExCup winner Brandt Snedeker (74), who both finished just outside the cut at 144.
U.S. Open winner Martin Kaymer of Germany soared to a second-round 77 for 148. (Reporting by Larry Fine; Editing by Gene Cherry)