* A local football preview special on WJLA.

* A documentary on Greta Garbo on TCM.

* And the debut of "Go, Diego, Go!" on Nickelodeon.

Local Sports Special

Are You Ready? WJLA's Tim Brant hosts a live special from ESPN Zone previewing the NFL season, with emphasis on those wacky Washington Redskins (Channel 7 at 8).

Sports

Tennis. U.S. Open mid-round coverage (USA Network at 11 a.m. and 7 p.m., with a half-hour recap show at 12:35 a.m. on Channel 9).

Baseball. Toronto at Baltimore (CSN at 7).

Public Broadcasting

Wide Angle: Unfinished Country looks at Haiti's attempts to organize itself for presidential elections in November (Channels 22 and 26 at 10).

Cable Specials

Go, Diego, Go! The morning preschool show, starring Dora the Explorer's popular cousin Diego, an 8-year-old bilingual animal rescuer and nature expert, debuts in prime time (Nickelodeon at 8).

Garbo. Julie Christie narrates a documentary about the enigmatic Greta Garbo (Turner Classic Movies at 8).

Series

Tommy Lee Goes to College. With seven days until finals, Tommy helps his fraternity members stage their first prank (Channel 4 at 9).

Late Night

The Tonight Show With Jay Leno. With Samuel L. Jackson, Rachel Bilson and music by Lifehouse (Channel 4, 11:35).

Late Show With David Letterman. The musical guest is Rob Thomas (Channel 9, 11:35).

-- John Maynard

The TV Column will return.

Greta Garbo, here in 1927's "Love," is the focus of a TCM special.