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England's Justin Rose was left to reflect on another Masters disappointment after a second round 78 saw him slump out of contention.
The 27-year-old World number nine started the day leading at Augusta for the third time in four visits, but just as he had on the previous two occasions, he slipped up when the spotlight was on him.
The low point was a triple bogey eight at 15 after he found water despite laying up in two.
"The 15th was a 20-second lapse in concentration," Rose said after signing for a 36-hole total of two-over 146.
"In hindsight, I probably should have gone for the green. It was right on the limit, just one of those things.
"I laid up way too close to the green and the way they grow the grain into you, I had a bit of a tricky lie and no yardage.
"That was hard but that just proved the struggle. I struggled all day with my concentration. It was such a long round and coming in last was tough. There was a lot of noise and I felt I was struggling out there.
"Yet it could have turned around nicely for me. I had a birdie chance on the 13th and 14th with the par-five 15th to play. I felt good about playing my way back into the tournament."
Rose, who won the European Tour order of merit for the first time last year, will start Saturday's third round 10 strokes behind leader Trevor Immelman.
"Obviously there is plenty to play for but it's not the exciting weekend I was looking forward to," he added. "It was an exciting Thursday."

