Who has a 7.62 career ERA and every chance to be a big story this year? Phillies reliever Scott Mathieson. The 27-year-old righthander was a well-regarded starting prospect five years ago, before two disastrous cups of coffee in 2006 (7.47 ERA in nine games) followed by two Tommy John surgeries in a span of 20 months. Recast as a fireballing reliever—his fastball averaged 95 mph in two outings for Philadelphia last season—Mathieson ate minor league hitters alive in 2009 and '10, with a 2.14 ERA in 96 2/3 innings and a strikeout rate of 30% of batters faced. Concerns about his command persist, but the Phillies need to integrate new blood into their bullpen: The top five relievers are all at least 30 years old, and only Ryan Madson had a sub-3.00 ERA last year. Charlie Manuel likes his guys; it's high time he started liking other ones. Mathieson, along with righthander 23-year-old Vance Worley (two runs allowed in 13 innings as a call-up last year) and 28-year-old lefthander Mike Zagurski (11 strikeouts in seven big league innings in '10), can give an aging pen some youthful vigor.