"I am wasting my time here. If I didn't have a contract I might have gone home - I still might," said Montgomerie, the defending champion, who bogeyed the last to slump nine shots behind the leader, Scott Henderson.
Montgomerie exploded after reading an apology from the organisers of the tournament for the state of the greens. The letter, sent to all the players, admitted there had been a greenkeeping mistake, which had exacerbated damage caused by bad weather.
Montgomerie's problems on the greens left him with five bogeys for a one-over-par 72 and a five-under-par total of 137.
While Montgomerie seethed, Faldo - his playing partner at previous Ryder Cups and his expected pairing at Valderrama in three weeks' time - flourished.
Faldo, a wild-card choice by the Ryder captain, Seve Ballesteros, shot 65 to haul himself up the field into second place on 131, three shots behind Henderson.
"I'd really like to win this week for a good little boost before the Ryder Cup," Faldo said. "It's an exciting time of the year after not such a good spell and I'm looking forward to the cup where we find ourselves in a transition with this team.
"The old guard, Sam Torrance, Mark James and Howard Clark, for instance, have gone and we've got an influx of good new blood."
Henderson took over from the first-round leader and his fellow Scotsman Gary Orr, whom he had trailed by a stroke overnight, with six birdies for a 66. Orr hit a birdie early in his round and ended the day sharing second place with Faldo on 11 under par.
Scores, Digest, page 27