When the news broke that Dick Schofield had been traded from the Yankees to the Dodgers in early September, it was quickly swallowed up by the yawns of millions of Americans. Last week, however, Schofield jolted every red-blooded pennant watcher wide awake with his performances. He began by getting four hits in an 8-3 victory against the Mets. Then, in a showdown series against the Pirates for the league lead, Schofield ignited a five-run rally for a 5-3 win and contributed to a three-run outburst that paid off with a 5-1 victory. After four games as a Dodger, he was hitting .437. Moreover, his fielding at third base had helped preserve a 1-0 win over the Astros. All of which was not bad for a player who had a .155 average with the Yankees and a .232 lifetime mark. For Schofield such achievements under extreme pressure are nothing new. When Shortstop Dick Groat was hurt late in 1960, it was Schofield who came off the bench, batted .386 in 19 games and helped carry the Pirates to the pennant. Alas, Schofield's efforts have been meteoric: a burst of brilliance, then a quick fadeout. But, above all, Schofield is a competitor and, prodded by his own feverish energies and �lan, he has always been a hustler, even when working out with the scrubeenies. "I always work hard," is his simple explanation. Such preparation paid big dividends last week as the Dodgers, with a big lift from Schofield, took a strong grip on first place.