Sox relying on unlikely leaders

No hitter on the Boston Red Sox -- or perhaps in the American League -- matched David Ortiz's production in April.

Yet, when the Red Sox look back on April, it will be the contributions of Mike Aviles and Ryan Sweeney most associated with keeping the team afloat.

Five months ago, both seemed destined for bench roles in a loaded Boston lineup. Through the attrition of trade (Marco Scutaro) and injury (Jacoby Ellsbury and Carl Crawford), not only have they been pressed into regular roles, Aviles and Sweeney are Boston's newest 1-2 punch atop the lineup.

As Darnell McDonald and Jason Repko regularly saw turns in a once-potent lineup, the spark from Aviles and Sweeney allowed the Red Sox to weather the storm. Only Ortiz (15) had more extra-base hits than Sweeney (12) and Aviles (11) in April.

In the past six months, Aviles has gone from projected utility player to the second-most productive shortstop in the league. Among shortstops, only Derek Jeter had a higher OPS in April.

While Scutaro has just one run batted in this season, Aviles (17 RBIs in April) is driving in runs at a furious pace. Over the past 50 seasons, only two Red Sox shortstops have had more RBIs through 23 games: Rico Petrocelli (21 in 1970) and Nomar Garciaparra (20 in 1998).

Aviles' biggest contribution has come as a leadoff hitter in place of Jacoby Ellsbury. Since moving into the leadoff spot on April 14, Aviles is hitting .304 with a .937 OPS. Since that date, only Derek Jeter has a higher OPS among AL leadoff hitters.

Whether it's taking over at shortstop or atop the order, Aviles is making the most of his opportunities.

Consider that he's hitting just .197 with the bases empty this season. His success has come courtesy of a .556 batting average (10-for-18) with runners in scoring position, the highest in the majors. His 1.300 OPS with men on base ranks second in the AL.

So how's he doing it? Aviles is crushing off-speed stuff. He's 12-for-28 (.429) on at-bats ending in a change-up or curveball, a key to his success against right-handed pitchers. In the previous three seasons, he hit just .237 on those pitches.

The big question surrounding Aviles was his defense. He hadn't been a regular shortstop since his failed 2009 season. Thus far, he's exceeded expectations. Aviles has three defensive runs saved, tied for the most on the Red Sox and fourth among AL shortstops.

If Aviles was a pleasant surprise, Sweeney's April seems unfathomable. A .283 hitter entering this season, he finished April with a .373 batting average. That was the highest in April by a Red Sox right fielder (min. 40 plate appearances) since Tony Conigliaro in 1965.

On a team accustomed to prolific doubles hitters, Sweeney is smacking them at an almost unprecedented pace. With an MLB-leading 11, he's already matched the doubles total from 108 games in 2011.

Sweeney hit his 11th double in Boston's 21st game. The last Red Sox player with more doubles in the team's first 21 games was future Hall-of-Famer George Kell in 1953. It's not just Red Sox history either. The last right fielder with more doubles through 21 games was Pat Mullin, who had 12 for the 1947 Detroit Tigers.

Most impressively, Sweeney has done it while sitting against left-handed pitching. That means he finished April with 11 doubles in 16 starts.

Boston entered the season figuring right field couldn't be any worse than it was in 2011, when the club got a .233 BA and .652 OPS from the position. Consider that the Red Sox didn't get their 11th double from right fielders until after the All-Star break.

Sweeney is getting it done by attacking pitches early in the count. Last season, Sweeney didn't have a single first-pitch hit. This season, he already has two, including one of his doubles. Sweeney is hitting an MLB-best .727 within the first two pitches of a plate appearance. His eight hits within the first two pitches is already more than half of the 15 he had in 2011.

Sweeney finished April batting .447 on at-bats ending in a fastball. As with most left-handed hitters who find success in Boston, Sweeney has been driving the ball to the opposite field. His eight opposite-field doubles are tied with Joey Votto for the most in the majors.

If the Red Sox outfield ever gets back to full strength, Sweeney has made a case for himself as the regular right fielder against right-handed pitchers. He finished April hitting .414 against them, third highest in the majors behind Michael Bourn and Paul Konerko.

Lefties are still another story. A career .588 OPS against them, Sweeney is just 1-for-9 against left-handers this season.

The irony is apparent, as the Red Sox get key contributions from Aviles and Sweeney. Aviles came from the Royals last July to serve as infield depth. Sweeney was seemingly a throw-in when the Red Sox acquired Andrew Bailey in December.

While big-name free agents like Carl Crawford and John Lackey languish on the disabled list, it's a pair of under-the-radar acquisitions pacing the club.

Jeremy Lundblad is a senior researcher with ESPN Stats & Information. He provides statistical analysis for ESPNBoston.com.