By MARK HALE



August 28, 2007 -- It's getting encouraging for Pedro Martinez, and with potentially one final rehab start remaining, the Mets' ace is absolutely looking impressive.
Martinez had another strong rehab outing last night, his fourth, firing a six-inning 88-pitch effort for Single-A St. Lucie. Facing Palm Beach, he allowed only an unearned run on five hits, two walks and a hit batter, while striking out four. He told The Associated Press afterwards that he "felt good overall."
Martinez, who was also excellent in his previous rehab start, evidently isn't returning to the Mets just yet, though.
"Pretty safe to say he's going to make another [rehab] start," Willie Randolph said before Martinez's outing last night.
Said Martinez to the AP, "I'm going to let the medical staff and Omar [Minaya] make that decision."
Martinez, who's pitched a total of 18 minor-league innings in rehabbing his torn rotator cuff, was expected to need a minimum of four rehab starts and a maximum of five. Assuming he has a fifth - which would figure to be over the weekend - then the earliest he could return is next weekend at Shea Stadium against the Astros.
Martinez's pitch count is rising - he jumped to the 88 mark after throwing 72 pitches in his last outing. He threw 52 strikes in both starts. In his last outing, Martinez allowed no earned runs on two hits in five innings for St. Lucie. Each of his four rehab outings has been in Single-A, though Minaya has said that pitching at Double