Colin Montgomerie said he was pleased to have some extra time off after missing the cut at the Wales Open.
The Scot carded a second-round 75 for eight-over par, 19 shots off the lead held by Italy's Alessandro Tadini.
"I'm very tired but I've got nine days off now and I'm looking forward to that," said Montgomerie, who qualified for the US Open last week.
"I'm hitting the ball OK but I just didn't score very well. If you're not on your game this course is not easy."
The Scotsman, who began the day on two-over par, birdied the 10th, his first hole, but dropped four shots in three holes before the turn.
The 41-year-old birdied one more, but also bogeyed another, to end the round knowing that it was highly unlikely he would play any further part in the Celtic Manor competition.
"The first target was getting back into the top 50 and the next one is to be in the top 25 by the end of the year," added Montgomerie, who reached the first mark after finishing 11th at Wentworth last week.
"I have to look towards that and there are six big tournaments coming up, starting with the US Open, and I'm looking forward to them all."