From the old school (home runs, batting average, runs batted in, wins, earned run average) to the money ball school (on-base percentage, slugging percentage, wins over replacement player), there's more to feed the stat geek's appetite than ever.

FORBES

Last December in-form playmaker Xavi tore his cruciate ligament, but former youth team player Andres Iniesta emerged as an able replacement.

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Back-row replacement Andy Powell proved his value as an impact player with some powerful running, but Toulouse continued to threaten as the minutes ticked away.

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The closest way, perhaps, is to look at wins above replacement, which attempts to capture the contributions of each player to his team and its win total.

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The numbers are based on FanGraphs' projected 2012 wins above replacement (WAR), a statistic used to compare a player's value to the average Triple-A fill-in.

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Owen Farrell, 17, became the youngest English top-flight player since union went pro as a 67th-minute replacement.

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Hayman made his Test debut as a replacement for Greg Somerville against Samoa in 2001, becoming the 1, 000th player to represent the All Blacks and has gone on to win 35 caps.

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Fast bowler Shaun Tait, a late replacement in the side who finished the World Cup with 23 wickets is just one example of a young player slotting straight into the team.

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The versatile Sale player can cover full-back, wing and outside centre, and if used as a replacement, could provide more of a cutting edge to a back division that has struggled to create chances.

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