CHANG STRUGGLES INTO SEMIFINALS.

Byline: Daily News Wire Services

It never seems to be easy for Michael Chang.

In the first men's quarterfinal at the U.S. Open on Wednesday, No. 2 seed Chang held on to beat unseeded Javier Sanchez of Spain 7-5, 6-3, 6-7 (2-7), 6-3. That Sanchez was in the quarters at all was remarkable, considering he is ranked 67th in the world.

``I never have easy matches against the Sanchezes,'' said Chang, who would move to No. 1 in the rankings by winning the U.S. Open singles title. ``It's pretty fair to say they are all great fighters and competitors, and I'm not just referring to Emilio and Javier. Obviously, Arantxa (Sanchez Vicario) is in the same category. I'm just glad I could get by him.''

A California-reared Nevada resident, Chang's success this year in the borough of Queens perhaps justifies the USTA's rejiggering of the seedings that caused so much controversy at the beginning of the fortnight.

Chang next faces Andre Agassi who advanced with a 6-2, 7-5, 4-6, 6-2 victory over Thomas Muster of Austria.

Chang has never put his trust in tricky shots. He would rather win the hard way, settle into a five-set epic the way most people settle into a hammock, outwait his opponent over the long haul, put in overtime without a complaint.

So it was surprising when he resorted to trickery against Sanchez, a player who had stumbled in the first round of all three other Grand Slams this year and was burdened by an 0-3 record against Chang.

Eager to take a two-sets-to-none lead after scrambling out of a 4-5 deficit in the first, Chang converted the set with a madcap flourish: He sent Sanchez a backhand drop shot that took a short standard hop on the Spaniard's side of the net and then, propelled by its underspin, hopped back over the net, with Sanchez leaping in pursuit, and bounced again on Chang's side. Chang, who pretended to be oblivious to the whole spectacle, had his lead.

But Sanchez refused to be stumped in straight sets. Down two breaks in the third, he fought back and broke Chang in the fourth and eighth games, and suddenly what had seemed a sure thing for Chang grew as murky as the haze over the stadium.

When the third set went to a tiebreaker, Chang didn't go with it. Instead it was Sanchez, fueled by his 15-7 record in that specialty this year, who sprang out to a 5-0 lead.

A wild backhand from Chang gave the Spaniard a set point at 6-2, and he put it to good use by belting a pair of forehands that caught Chang off balance and provoked a forehand reply into the net.

Losing that set sobered Chang, and he closed out the match in the fourth set with a careful application on controlled aggression, much of it delivered in the form of court-opening forehands struck deep to Sanchez's backhand corner.

It is just the second time in 10 Opens that Chang has reached the semis. The last time, in 1992, he played a five-set, 5-hour, 26-minute match before losing to Stefan Edberg, who went on to win the championship.