"I'm gonna hit three home runs in this ball park," said Reggie Jackson of the Oakland Athletics as he feasted his eyes on Boston's Fenway Park last week. Why the sinistral Jackson was so optimistic about batting in a righthander's haven defies explanation; what he did, though, almost defied the ages In Saturday's game he drove in 10 runs He began by doubling across one run in the first inning, then hit two-run homers in the third and fifth, batted in two runs with a seventh-inning single and three more in the eighth with a bloop single. Jackson's 10 RBIs fell one short of the American League record set in 1936 by Tony Lazzeri of the Yankees and two shy of the major league mark established in 1924 by Jim Bottomley of the Cardinals. A strikeout with the bases loaded in the sixth cost Jackson the record Ironically, a lack of strikeouts caused Jackson to miss another record last year His 171 strikeouts came within four of the alltime high set by Dave Nicholson of the White Sox in 1963 But the big record—Roger Mans' 61 asterisk homers—stands well within the reach of the big (6'2", 195 pounds) 23-year-old outfielder from Wyncote, Pa. Jackson, who followed up his big day with a double, triple, home run and four more RBIs the next afternoon, has 23 homers, one more than Babe Ruth at the same stage in 1927, and three more than Maris in 1961 Rico Petrocelli of the Red Sox and Willie McCovey of the Giants, with 20 and 21 homers, respectively, are right behind Petrocelli has a calcified elbow, McCovey an arthritic knee and Jackson, not to be outdone, football knees and an arthritic spine. If all three feel rotten enough, this should be some race for baseball's golden record.