Something surprising probably is going to happen in the National League West. But what in the world will it be?

The San Diego Padres, one of the least impressive teams in a World Series in recent times, look very vulnerable. The mystery is who'll catch 'em.

Two parallels come to mind: the two most recent National League champions.

The '83 Philadelphia Phillies were too old and got embarrassed in five games by the Baltimore Orioles. They promptly faded to fourth place. The Padres depended on Goose Gossage, Graig Nettles and Steve Garvey, who helped pull off one last pennant roundup but showed signs of age. The Padres were also exposed in a five-game Series.

The Phillies, sensing their weakness, made bad trades before the next season and San Diego might have, too.

The 1982 St. Louis Cardinals were the first team to win a pennant without a pitcher with more than 15 victories or a hitter with more than 20 homers. The Cardinals have gone down ever since. The '84 Padres were the second such team.

Last season, the Padres' two 20-homer men were Nettles and rookie Kevin McReynolds. Nettles has looked his age this spring -- 40. And McReynolds isn't entirely recovered from a broken wrist. Young Carmelo Martinez did so little the last two months that he has to prove the league hasn't solved him. When you consider that Terry Kennedy and Garvey are coming off terrible power years (14 and eight homers), you wonder how San Diego can match its 686 runs of '84.

The Padres' pitching rotation, a national laughingstock in the playoffs and World Series, hardly seems improved. Ed Whitson (14-8) went free agent. Tim Lollar (11-13) was dealt for 18-game loser LaMarr Hoyt, who's had such an erratic career it would be rash to guess his future; he's no 24-game winner. And 15-game winner Eric Show could be seriously shaken by his disastrous postseason.

The Padres had enough of everything but not a whole lot of anything last year. They also beat a division in which everybody else had a losing record.

San Diego has wonderful, almost unheard of, depth in its bullpen. General Manager Jack McKeon is his league's slickest operator at the moment and Dick Williams hasn't frayed his club's nerves yet.

But these guys can be had.

Probably by either the Atlanta Braves, with Bruce Sutter in the bullpen, or by the Houston Astros who, now that the Astrodome fences have been moved in, will have surprising 120-homer power.

The Braves blew eight ninth-inning leads last year. That shouldn't happen again. Also, their pitching staff could round into fine shape. Pascual Perez (14-8) will be available all year. Rich Mahler (13-10) is strong. Heat man Steve Bedrosian now is a starter and should never need to go more than seven innings. With Rick Camp in long relief and Gene Garber behind Sutter, and with Craig McMurtry or Len Barker to fill out the rotation, the Braves can pitch.

But can they hit? When you play in the Fulton County launching pad and end up eighth in the league in runs, you need a war-club transfusion. The Braves were outhomered, 72-53, in their phone booth last season and no help appears on the way. Slugger Bob Horner, his career jeopardized by a repeatedly injured wrist, is a total question mark; he seems to be rushing back. Dale Murphy, who tied for the league lead in homers, already has maxed out and probably can't give more. Chris Chambliss has had another birthday (36) and no Atlanta catcher has had 10 homers or 50 RBI since Earl Williams in 1972.

If Horner hits 25 homers, the Braves should win. If not . . .

Trivia quiz: what National League team finished second to the homer-happy Phillies in road homers last year?

Answer: the Astros, who hit 61 on the roam and 18 in the Astrodome.

Now, the miserable Astrodome finally has semi-normal dimensions. Watch Jose Cruz (.344 home, .276 road), Enos Cabell (.348 vs. .269), Alan Ashby (.313-.207) and Billy Doran (.288-.232) start smiling. And watch everybody discover the long ball, especially Cruz who, at 36, finally has one chance to play in a normal park and show he's the most underrated hitter of his time.

More power is vital because the Astros no longer have speed (11th in the NL). If Houston, which has played .372 ball for the last four Aprils, can finally avoid stumbling out of the blocks, it should be in the race all year.

If so, the Astros' bullpen -- with Bill Dawley, Frank DiPino and Dave Smith -- could be decisive; the pen ERA was 2.63 in '84. The Houston flaw is -- surprise -- the starting rotation that was the league's envy for years. Joe Niekro is 40, Nolan Ryan 38. Bob Knepper has gopheritis and won't like the new fences one bit. And who, pray tell, are the No. 4 and 5 starters?

What will happen to the fading Los Angeles Dodgers, the slightly revived Pete Rose Reds of Cincinnati and the totally inexplicable San Francisco Giants? It's a conundrum that could be more difficult than it is interesting.

Any team with Fernando Valenzuela, Bob Welch, Orel Hershiser (2.66), Rick Honeycutt (2.84) and Jerry Reuss in its rotation certainly is capable of more than 79 victories. Despite the Dodgers' wealth of arms, their hitting is so awful that The Blue looks like a long-shot contender, at best. The Dodgers were last in baseball with 580 runs, 249 behind Detroit.

The L.A. middle infield suspects -- Steve Sax, Dave Anderson, Bill Russell, Bob Bailor -- totaled four home runs last year.

The Dodgers' best hope is that their '84 plunge to fourth place can be excused because of the constant injuries that forced Tommy Lasorda to use 103 lineups. The L.A. key: find a first-inning lineup that can get a few early leads. Sax was the worst leadoff man in the NL and the Dodgers scored only 63 first-inning runs all year. The Cubs had exactly twice that.

In this muddled division, either the Reds or Giants can create mild surprise by moving up near .500.

Cincinnati played 19-22 ball under Rose last year and the 44-year-old dynamo will find ways to get his young pitching staff to win a few games. His real double-edged sword is his quest for 95 more hits and Ty Cobb's career record of 4,191.

If Rose, who hit .365 in 96 at bats in Cincinnati last year and has just had a short, torrid spring in Florida, plays with distinction, the whole team could be inspired by his example and invigorated by the attention it brings. However, if Rose becomes a pathetic figure as a player, won't it dilute his credibility and his assets as a manager?

San Francisco has an outstanding outfield of Chili Davis, Jeff Leonard and Dan Gladden, plus a top hitting catcher (Bob Brenly -- .291). However, the Giants have a miserable defense, especially on the left side of the infield, which exposes all the flaws of the league's worst pitching staff.

If the Giants, who'll now mercifully play three-quarters of their home games in the afternoon, are to avoid 90 losses, they'll need help from new starters Dave LaPoint and Jim Gott plus an unlikely comeback from '83 ERA champion Atlee Hammaker, who's had both rotator cuff and elbow surgery.

The combination of bad defense, the trade of reliever Gary Lavelle and a rotation full of question marks probably means that the Giants' last year in San Francisco will be a disappointing one, despite a 700-run offense.

Did someone say, "Last year by the Bay?" One of the season's better bets is that the Giants will be sold, and probably moved, before Christmas.

To Washington, D.C.?

The picks in what could be a close three- or even four-team race where nobody wins 90 games: Atlanta, Houston, San Diego, Los Angeles, Cincinnati, San Francisco.