Roger Federer is often praised as the greatest tennis player of all-time; his game is aesthetically pleasing and technically precise and he has claimed a large portion of the sport's all-time record book--but Rafael Nadal, whose record-setting career is even more impressive than Federer's was at the same stage, has defeated Federer 23-10 in their head to head meetings. When Federer faces Nadal he does not look like the greatest player of his own era, much less the greatest player of all-time.
Peyton Manning is often praised as the greatest quarterback of all-time; his game is aesthetically pleasing and technically precise and he has claimed a large portion of the sport's all-time record book--but Manning has just an 11-12 record in playoff games, including 1-2 in Super Bowls after his Denver Broncos lost 43-8 to the Seattle Seahawks in Super Bowl XLVIII.
A tennis player battles one on one against his opponent in singles matches, while a quarterback is just one of 11 offensive players--but quarterback is the most important position in football, if not all of team sports, and a great quarterback can have a disproportionate impact on the outcome of a game. Manning has no problem making his presence felt during regular season play but his playoff record does not measure up to the postseason success enjoyed by Otto Graham (10 championship game appearances and seven championships in a 10 season career), Johnny Unitas (2-1 in NFL championship games, 1-1 in Super Bowls, 6-3 overall playoff record), Joe Montana (four Super Bowl wins in four appearances, 16-7 overall playoff record) and Tom Brady (three Super Bowl wins in five appearances, 18-8 overall playoff record). Terry Bradshaw was not as efficient statistically as Manning--though Bradshaw played in an era during which the rules heavily favored the defense, while the opposite is the case now--but Bradshaw went 4-0 in the Super Bowl and posted a 14-5 overall playoff record. Steve Young began his career in the USFL, played two seasons for a terrible Tampa Bay team and then spent several of his prime years backing up Montana in San Francisco but Young still assembled a 12-8 overall playoff record, including 1-0 in the Super Bowl. Kurt Warner has the same 1-2 Super Bowl record as Manning but Warner went 9-4 overall in the playoffs and he performed better in his three Super Bowls than Manning has.
Manning receives a lot of credit for "making his teammates better"--an ambiguous phrase at best in terms of defining an athlete's greatness--but even if we accept the very debatable premise that Manning has elevated mediocre teammates and/or teams to greatness during the regular season and thus deserves praise for doing so then don't we also have to assign some of the blame to Manning if those same teammates are nervous and/or tentative at the biggest moments? More to the point, Manning himself seemed nervous and tentative during Super Bowl XLVIII; although Manning set the Super Bowl single game record for completions (34) and threw for 280 yards, Troy Aikman commented during the telecast that it was difficult to remember when Manning accumulated all of those completions and all of that yardage: Manning's performance did not pass the eye test and anyone who watched the game analytically could see that Manning did not play at a high level, regardless of how one spins the numbers.
Furthermore, the idea that Manning has thrived despite being surrounded by lesser talent does not withstand close scrutiny. Manning's teams do not generally sneak into the playoffs only to lose to clearly superior squads; his teams race to tremendous regular season records only to stumble against lesser teams: Manning has lost his first playoff game (either in the Wild Card round or after enjoying a bye week) a record eight times. Just as it would be wrong to deny that Manning's gaudy regular season numbers have earned him a prominent place in the all-time quarterback pantheon, it would be wrong to deny that Manning's relative lack of postseason success (compared to several other members of that pantheon) strongly argues against placing Manning at the very top of the all-time quarterback list.
The title "greatest of all-time" may be largely mythical, something that is impossible to determine by purely objective means--but it is difficult to believe that someone with a glaring hole in his resume should be ranked ahead of great players who do not have a similarly glaring hole in their resumes. Is Federer one of the greatest tennis players of all-time? Of course. Is Manning one of the greatest quarterbacks of all-time? Of course. Federer never mastered his main rival Nadal--or even figured out how to play against him on close to even terms--so it makes no sense to label Federer as the greatest of all-time; Manning never dominated NFL postseason play--or even came close to matching the championship success of quarterbacks like Graham, Unitas, Montana and Brady--so it makes no sense to label Manning as the greatest of all-time. Super Bowl XLVIII did not hurt Manning's legacy, because objective observers already understood where Manning should be placed in the quarterback pantheon--but Manning's mediocre performance during Denver's loss represented a missed opportunity for Manning to add to his legacy. If Manning had been sharp while leading Denver to victory then he would have written another chapter in his story, much like Federer could have done if he had ever figured out how to deal with Nadal's relentless groundstrokes.