Los Angeles - Stunned golf fans at the Phoenix Open were left to ponder how the mighty have fallen after Tiger Woods plunged to new depths with the worst score of his professional career in Friday's second round.

Looking more like a struggling amateur than the greatest player of his generation, and arguably of all time, Woods was out-of-sorts in every phase of his game as he laboured to a mind-boggling 11-over-par 82 at the TPC Scottsdale.

His chipping, in particular, was poor and many pundits are now pointing to Woods, a 14-times major champion once renowned for his magical skills around the green, as being a sufferer of the 'yips' when it comes to that component.

Dottie Pepper, who won 17 times on the LPGA Tour, including two majors, tweeted on Friday: "Never fun seeing, let alone reporting on, 2 dreaded topics in golf: shanks & yips. Sadly, #Tiger has the latter. Nerves not mechanics."

Arron Oberholser, a PGA Tour player who also works as an analyst and commentator for Golf Channel, said: "I think the greatest player that I've ever seen has the yips.

"Whether that's because of a release pattern or whether it's not enough reps, it's flat out the disease. He's got the yips."

Woods had also struggled with his chipping in his previous tournament, last month's Hero World Challenge in Orlando where he tied for last place, and at Scottsdale he hit chips fat and thin while occasionally resorting to a putter instead.

Before any rush to judgement is made, however, it is worth emphasising that Woods was competing at Scottsdale in only his second event in five months, having endured back problems for much of last year after undergoing surgery.

He is also still adapting to the fifth swing change of his career, this time with new consultant Chris Como, and history will recall that Woods took a long time to reach the comfort level he wanted for each of his previous four overhauls.

"He's really revamping his golf swing and just seems like he needs some more repetitions," American world number nine Jordan Spieth said after playing the first two rounds at the TPC Scottsdale with Woods.

"From the looks of it, he looks very healthy, looks like nothing was bothering him, so he should be able to get out there and get a lot of practice in. I would look for him to make a strong comeback this year."

Others were not so optimistic on Friday after Woods, for the first time in his career as a professional, missed the cut in consecutive PGA Tour events, his previous one having occurred at the PGA Championship in August.

"I think he needs to get rid of Chris Como," Oberholser said on Golf Channel. "He needs to get rid of all of these biomechanic guys. You don't go to a biomechanic guy when you're the best guy who's ever played the game practically."

Woods, limited to just nine tournaments worldwide last year due to his back issues, has often struggled to take his game from the practice range to the golf course, and fellow PGA Tour player Colt Knost believes this is once again the case.

"I watched tiger hit balls for 30mins yesterday on the range and he absolutely striped it! Something is going on in that head of his," Knost tweeted on Friday.

After missing the cut at the TPC Scottsdale, Woods conceded that his chipping problems stemmed partially from a mental block.

"To an extent, yes it is, but I need to physically get the club in a better spot," said the 39-year-old Woods. "My attack angle was much steeper with (previous instructor) Sean (Foley).

"Now I'm very shallow, so that in turn affects the chipping. I'm not bottoming out in the same spot."

Time and again during his remarkable playing career, Woods has successfully overcome assorted challenges -- many of them injury-related. If yips are in fact his latest challenge, it would be foolish for anyone to write him off any time soon.