"If I felt right, I would continue to throw," Darvish said. "But I didn't, so I stopped throwing."
On Tuesday morning, the Rangers made the decision to send Darvish back to Texas for further examination. Darvish said the problem was caused because he slept wrong one night last week, but the organization is concerned that the problem might be more complicated than that.
"He has not shown the progress that we would like," assistant general manager Thad Levine said. "We want to start ruling out things at this point. At this stage, we're open to it being more than just sleeping wrong."
The Rangers also wanted to put a stop to any tendency to rush Darvish into trying to pitch on Opening Day.
"We want to get him right physically and mentally," manager Ron Washington said. "We don't want him out there trying to pitch, and in the back of his mind he knows something is wrong and he's trying to gut it out. We certainly don't have a target date on when he will pitch again. We'll just see where it goes."
There is a possibility Darvish could receive an anti-inflammatory injection that will hopefully clear up the problem.
"If I get an injection or acupuncture, it will heal right away," Darvish said.
The Rangers have made no announcement as to who will replace Darvish on Monday when they open the season against the Phillies at Globe Life Park. Martin Perez appears to be the leading candidate, but at this point, it could be almost anybody. Right now, Perez and Tanner Scheppers are the only two pitchers with spots locked up in the rotation, although Joe Saunders is expected to get a spot. Robbie Ross, Colby Lewis and Tommy Hanson are also still competing.
Darvish will likely start the season on the 15-day disabled list, but the Rangers could backdate it as much as nine days. That means Darvish could miss as few as the first six days of the season. The club won't need a fifth starter until April 8.
"We haven't had a chance to sit down and decide what direction we're going," Washington said.
Darvish had neck pain in Spring Training last year, but it was earlier in camp and he ended up being ready for the start of the season. He was on the disabled list last year from July 7-22 for a strained muscle in the back of his right shoulder but missed just one start because of the All-Star break.
"If it were a shoulder or an elbow, I would be disappointed," Darvish said. "This is something that happened when I woke up. I don't know if I should feel disappointed. It is what it is."
Two years ago, the Rangers opened the season with a rotation of Matt Harrison, Derek Holland, Neftali Feliz, Lewis and Darvish. All five are still in the organization, and Feliz, who is now a middle reliever, was optioned to the Minors on Tuesday so he can continue his recovery from Tommy John surgery.
Holland is out until June after undergoing surgery in January on his left knee. He has been throwing in camp and could start throwing off a mound next week in Arlington. Harrison is still recovering from his back problems of last year, and he pitched just three innings in his last start. He is scheduled to pitch on Friday in San Antonio, but it will likely be just three innings again. Harrison could need at least three more starts in the Minors on medical rehab assignment before being an option at the Major League level.
Lewis, who hasn't pitched in the big leagues since July 18, 2012, while recovering from flexor tendon and hip replacement operations, is scheduled to throw 75 pitches against the Mariners on Wednesday. Lewis will likely need at least one more start and possibly two before he's ready to pitch in the Major Leagues again.