Don Zimmer is smiling his paunchy smile these days, nervously. He sees his team only 3 1/2 games out of first place; the Yankees are an even 10 games behind the Orioles, and the resurrection of Billy Martin has not guaranteed New York its 1979 baseball kingdom. But still, there are lingering afterthoughts of the Red Sox in 1978, of that awesome 14 game lead at the beginning of September.

"We're not making any predictions, we're just playing," Zimmer said two weeks ago in the Sox clubhouse, and when you ask him to elaborate he merely repeats the same words.

And further insecurities are sprouting up at this moment, only days from an 11-star break. No one seems to believe that the Orioles can stay in first place much longer, but some people are beginning to think that Earl Weaver is the kind of manager who could drive his club to such a feat.

"Weaver is the kind of manager who can wring his pitching staff dry, and only have them running down by the Super Bowl," Red Sox pitching coach Al Jackson said last month.

If anything, the Red Sox are a more unified ball club this summer, deeper at every position lacking internal squabbles and peeves, and collectively more healthy. Only Carlton Fisk dangles on the injury list like a dark cloud, and his availability during the next two months could be crucial to the success of the '79 Red Sox.

But Fisk is not moping around the clubhouse too much. After facing Detroit last month, Fisk said, "Yeah, I batted like a limp fish today, but I'm not going to take it too hard, because the more you think about it, the more you will fall into a mental slump, and that leads to worse." Fisk also said that he will take his sore elbow through the season a "day at a time, because at this point I know its hurt, I don't really know how, and there's nothing I can do to make it better but take it easy and be loose.

Fisk's nonchalance is reflective of a new trend on the Sox, a feeling this ball club has not had for a long time. They're loose. They're not getting too excited, and this year, many of the players are apt to pick up a card game in the clubhouse instead of a newspaper.

And as the players loosen up on the field and in the clubhouse, there is the heavy spectre of Zimmer--Zimmer pacing; Zimmer rapt from the dugout; Zimmer with grimace; Zimmer shooting suspicious, beady eyes at the press from behind his desk in the clubhouse.

"I think people have to realize that this team is stronger than they were last year. We've got solid pitching, and more experience, and more depth, and we're healthier." One of Zimmer's more lucid moments, no doubt.

With Hobson, Burleson and Lynn healthy, the Red Sox are twice as potent. And the Red Sox have recently acquired what they have needed for a year--a new first baseman. Though George Scott recalls memories of golden gloves and home-run rallies, it was apparent last March that Scott's best years had come and gone. He came to spring training in 1978 grossly overweight, and though he lost some pounds this winter, he never got his needle back on true north.

While Bob Watson--Scott's replacement--was belting drives and hits and homers for the Sox, Scott executed the old "George Scott double play" with startling timing and precision against his old teammates yesterday. While this may delight Fenway's dregs, some of whom managed to turn "Boomer" to "Boomer," it is a sad sight to behold, and an uglier one to hear. But it is better for George Scott and better for the Red Sox, who no longer have to rehabilitate old muscles, but must take care that their new ones stay in shape.