As coach Mariano Duncan Nalasco (born March 13, 1963) is a Dominican former second baseman and shortstop who played for the Los Angeles Dodgers, Cincinnati Reds, Philadelphia Phillies, New York Yankees, and Toronto Blue Jays of Major League Baseball and the Yomiuri Giants of Nippon Professional Baseball during his 12-year career.

In his rookie season, July 6, 1985, vs. St. Louis Cardinals, Duncan accomplished the rare feat of bunting for a double where the ball was untouched and did not roll beyond the base paths.

Duncan was traded by the Dodgers to the Cincinnati Reds with Tim Leary on July 18, 1989 for Lenny Harris and Kal Daniels.

On July 6, 1997, Duncan and Kenny Rogers were traded to the San Diego Padres for Greg Vaughn and two minor league players.

[7] Duncan was traded to the Toronto Blue Jays on July 29, 1997 for minor leaguer Angel Ramirez.