DETROIT

At first glance the Tigers look too good to be true. Jack Morris (20-13) is throwing three effective pitches (fastball, forkball, slider) for the first time, and Dan Petry (19-11) is developing a split-finger fastball to complement his terrific slider. Three Gold Glovers, catcher Lance Parrish (27 homers, 114 RBIs), second baseman Lou Whitaker (.320) and shortstop Alan Trammell (.319), bring excellent offensive credentials to defense-oriented positions, and centerfielder Chet Lemon (24 homers) is another fine two-way player. "If any team's as good up the middle, I haven't seen it," says manager Sparky Anderson. What's more, the Tigers snatched baseball's most popular free agent, Darrell Evans, age 36, from 17 other clubs. A first baseman who can also play third or DH, Evans hit 30 homers in windy Candlestick Park and could top that in cozy Tiger Stadium.

Yet the Tigers need even more help if they are to win their first division title since 1972, because no team in either league has such stark contrasts. Being good up the middle isn't enough if you've got serious weaknesses on the sides. Marty Castillo and Howard Johnson will platoon at third, most likely without distinction. Left-fielder Larry Herndon hits with the best (.302, 20, 92) but fields with the worst (a league-leading 15 errors). Rightfield has gone by default to Kirk Gibson, who has never lived up to his hype as "the next Mickey Mantle." Coached this spring by Hall of Famer Al Kaline, the lefthanded Gibson learned to play close to the line— he has trouble reaching across his body— and to play deeper to better handle long flies. But there's no camouflaging his disappointing bat. No. 3 starter Milt Wilcox has won and lost between nine and 13 games in each of the last six seasons, and No. 4 starter Juan Berenguer (9-5) "has to be pumped up every day," according to pitching coach Roger Craig.

The most significant improvement must come from Aurelio Lopez and Dave Rozema, who accounted for a mere 20 saves last season. Rozema has an excellent fastball, but he tends to overuse it while warming up; he has never lasted a full season in relief and still hasn't fully recovered from knee surgery two years ago. Lopez, who had only two saves in August and September, isn't considered durable. "We need three or four guys getting 12 to 15 saves apiece," concedes Craig. One of them could be former Phillie Willie Hernandez. The Tigers will win a lot without winning it all.

The night-prowling Tigers were .616 under the lights but .460 in day games. Base stealers had less success against Detroit than against any other AL club, being safe 56% of the time (the league average was 67%). But 170 opponents made it around the bases the easy way, as Tiger pitchers gave up the most homers in the majors.