The closest red line station, yikes. Probably Union Station? Seems like a long walk. We've taken the Circulator bus there before and after a game, but that's worse than walking to Cap South and transferring at Metro Center.
Might try walkng it some day when the weather's nice and it's not dark.
Edit: 35 minutes according to Google Maps. Cap South is 18, so it's about the same distance again.
I walked from Union Station to one of the hotels by the stadium last month for the M&G. Not too bad of a hike. Would've been better if it wasn't mid-90s, humid, not a cloud in the sky, no breeze and I wasn't lugging a suitcase.