Baltimore Orioles second baseman/outfielder Terrin Vavra slugged his first career big-league home run in his Club's 5-4 win in the first half of yesterday's doubleheader with the Toronto Blue Jays. The 25-year-old prospect has been a great defensive resource since his debut on July 29, playing in both the infield and outfield, but had yet to leave the yard until yesterday afternoon. Vavra's eighth-inning, three-run blast provided the go-ahead runs for the team's 83rd win of the season.