There is some concern nowadays about the fact that the Phillies have a losing record against winning teams.

Well, 1) judging from the past two years, that's not uncommon for contenders, and 2) based on last year's playoffs (SSS, I know) having a losing record against winning teams is not a major handicap. 

The 2010 full year records vs. winners and losers, as well as the 2011 records to date, are included after the jump.  Below are some highlights:

2010 records
(based on teams' final records, not what they were when they played each other; excludes interleague)
- 4 of the 8 playoff teams had losing records against winning teams
- of the 4 NL playoff teams, only the Phillies had a winning record against winning teams
- both World Series teams had losing records against winning teams
- the Reds really were very bad (.340) against winning teams

2011 records
(based on their records today, not what they were when they played each other; excludes interleague)
- the Phillies are .435 vs. winners, .727 vs. losers
- other contenders with similar records: Tigers .474/.679, Yankees .471/.700, Cards .467/.595
- the White Sox have a .367 record against losers

2010 records vs. winners (finished >= .500) and losers (<.500)
*** denotes playoff teams

2011 records vs. winners (currently >= .500) and losers (<.500) - through Mon 6/20