Jimmy Connors, who last year took the exit marked "semifinals" in the five most important championships of modern tennis, will play defending champion John McEnroe on Sunday in the final of the $250,000 World Championship Tennis playoffs, which this year is sadly a major event in name and reputation only.

Connors, who has settled into a comfortable fighting weight of 154 pounds, was just a bit too strong and too quick for Ivan Lendl, 20, and beat the improving Czech today in their semifinal match, 6-4, 7-5, 6-3.

In the evening semifinal, McEnroe was in dire trouble against the fleet, flashy but erratic Johan Kriek before winning, 6-4, 4-6, 7-6, 6-3.

McEnroe came back from 1.5 down in the third set to win it in a wild tie breaker, then held on after Kriek erased a 0-3 deficit in the fourth set and had a point for a 4-3 lead.

McEnroe -- who nearly lost control of the match when his usually intimidating serve went haywire at the end of the second set and start of the third -- will face Connors for the $100,000 first prize. Last year, the 20-year-old left-hander beat Connors in a scintillating five-set semifinal, and Bjorn Borg in a four-set final.

Connors' only anxious moment this afternoon came in the second set when his forehand went temporarily AWOL, especially on the approach shots off short, soft balls that have long been the 27-year-old left-hander's chief bugaboo.

Connors played a dreadful game to lose his serve at 2-1 -- the only time in the 2-1/4-hour match that Lendl broke him -- and had to scratch and scramble the rest of the set before breaking through at 6-5.

This battle was fought mostly from the backcourt on the medium-slow synthetic surface at just-opened Reunion Arena. Connors had more depth and pace on his groundstrokes, and was able to run down more balls.

He also attacked with more assurance when he had the chance, going to the net increasingly in the latter stages of the match as Lendl's shots grew shorter and more attackable.

It was a rather tedious match for the most part, sculpted far more by errors than winners. Both players did a lot of running ("Every time I play him, I wear out a pair of shoes," said Connors), but Lendl never seemed to have any more realistic hope of getting ahead than Rosie Ruiz did of beating Bill Rodgers in the Boston marathon.

Connors had won his previous two meetings with Lendl in straight sets. But this match promised to be more competitive. Lendl has been playing confidently and well since reaching the final of the Volvo Classic in Washington in March. He has moved up to No. 13 in the computerized world rankings and has displayed unmistakeable potential.

He is not there yet, however -- and that fact sums up the problem with this year's WCT Finals. Intended as a springtime showdown for eight of the world's premier players, the climatic playoff of the eight-tournament WCT circuit, "Dallas" this year has attracted only two of the current top 10: No. 2 McEnroe and No. 3 Connors.

The rest of the so-called "Exceptional Eight" consisted prmarily of young, promising, but as yet unproven players, ranging from Lendl to Heinz Gunthardt of Switzerland. Ranked No. 33, hapless Heinz put on a sorry performance in losing to McEnroe, 6-2, 6-1, 6-0 on Thursday night.

WCT's tub-thumpers -- trying to make chicken salad out of chicken feathers -- understandably promoted this year's field as the "wave of the future."

Unfortunately, however, the newcomers to Dallas have played, for the most part, like mere shadows of their future selves. John Sadri, Vijay Amritraj, Bill Scanlon and Gunthardt all failed to win even one set in the disappointing quarterfinal round.

And so it was with Lendl today -- flashes of talent, a brilliant winner here and "get" there, but no glue of consistency to hold the pieces together. "Maybe I wanted to make too big shots," he said afterward. "Maybe I should try safer shots."

Lendl had looked strong in whipping the badly off-form Amritraj in his opening match, but today it was his turn to appear wooden, sluggish, listless.

In the first set, his timing was way off. In the first game he mis-hit a lob 25 feet over the baseline and into the seats. Other mis-hits followed. He was regularly hitting his backhand late. When he tried to smack it down the line, it usually wound up in the doubles alley.

Those in the sparse matinee crowd of about 4,000 spectators -- who seemed lost and sleepy in the vast, new 19,000-seat arena -- had hoped to see an emerging Ivan the Great. Instead, they watched Ivan the Terrible.

Lendl lost his serve on four errors in the third game, that was on set. He lost it again in the third game of the second set, but by then his groundstrokes had more sting, and he was hitting more accurately. When Connors' forehand took a leave of absence, Lendl got back into the match by hammering at that side.

Curiously, though, he did not keep attacking that vulnerable flank, and Connors pulled away.

Lendl lost his serve in the 11th game. At 30-all, Connors slid a backhand approach down the line, tailing it away from Lendl's backhand, and moved in to put away a forehand volley. The break came on a fierce rally, Connors reaching a sharply angled cross-court shot, answering it with a similarly angled backhand, then intercepting the reply with a lunging backhand volley.

At the end of that point, Connors flopped onto his back and lay on the court as if dead from exhaustion.

"I was tired as hell. I couldn't believe it," he said later. "I was lucky to make that volley . . . I happened to be there, stretched out the right way."

After Connors served out the set Lendl started pushing the ball and offered little resistance in the third set. He lost his serve in the third game again, took only one point on Connors' last three service games, and lost his serve once more for the match.

Connors -- who started the year at 145 pounds, but is hitting with more power after gaining nine pounds -- was pleased with his effort. He is eager to regain titles that eluded him last year, when he lost in the semifinals here and at the French Open, Wimbledon, the U.S. Open and the Grand Prix Masters.

He says he is getting physically stronger with every match, and is serving better after making adjustments in his toss and service motion -- although he got only 55 percent of his first serves in the court today.

He says he has found peace of mind and renewed dedication to tennis now that he is settled into family life. Last year, he explains his attitude on the court was clouded by concern for his wife, former Playmate of the Year Patti McGuire, and his son Brett David, born Aug. 1.

"I'm playing much better than last year -- a big improvement," he said. "I only held my own last year. It was a mediocre year for me, tennis-wise, and I wasn't satisfied with that at all. . . . But if I continue going at the pace I am now, it shouldn't be very long before I'm pretty much completely satisfied with my game."

McEnroe seemed comfortably in command of his match against Kriek when he had a break point for a 5-4 lead in the second set, but he briefly let things get away from him as the large evening crowd of 14,000 got vocally behind the underdog.

Kriek broke McEnroe for the set with three great shots -- two passes on the dead run off balls that seemed impossible for him to reach -- around a McEnroe double-fault.

McEnroe double-faulted twice in losing his serve in the second game of the third set, and Kriek -- dazzling the crowd with his speed afoot -- sprinted to a 5-1 lead.

But Kriek is ranked only No. 28 in the world, largely because his patches of spectacular play are almost inevitably neutralized by double-faults -- he served 17 tonight -- and careless errors. He can net a simple volley as easily as he hits a passing shot on the fly. He doesn't seem to have the will to put away the worlds best players, and his risky style gives him a convenient "out" afterward.

He double-faulted and overhit an elementary backhand volley to start his slide back from that commanding 5-1 lead in the third set, and lost the second break on another double-fault.

"I should never have lost that set," he said later. "I went for it, and I flopped. I'd rather lose that way, going for it, than holding back and playing safe."

McEnroe won the pivotal third set tie breaker, 7 points to 3, after a dispute on the first point led to a 10-minute delay in play.

On that point, Kriek served and McEnroe hit a blazing forehand down the line that was called wide. He thought it was on the line and appealed to the umpire, who overturned the linesman's call. Kriek and the crowd were infuriated, a commotion ensured, and it was 10 minutes before the audience quieted enough for McEnroe to serve again.

When he did, he won two easy points on his serve, and got to 4-0. Having closed out the tie breaker, McEnroe broke Kriek at love and took a 3-0 lead in the fourth set. He had a point for 4-1 on his serve, two points for 4-2, but Kriek kept challenging him and got to advantage on McEnroe's serve at 3-3.

Here McEnroe, whose mobility was slightly inhibited by a sprained left ankle, leaned back and got out of trouble with a service winner down the center. That was the spark he needed to ignite a final burst, and he won the last three games -- surviving a match on a night that he did not serve or volley well.