Alex Rodriguez has accumulated some impressive statistics in his 11 seasons with the New York Yankees. These statistics include 333 home runs, 1,505 hits, 1,042 RBIs, a .290/.385/.534 slash line, and a OPS+ of 141, according to Baseball Reference. Rodriguez's production since the start of the 2004 season is only comparable to a few elite players, such as Albert Pujols and Miguel Cabrera.
In 2004, Rodriguez made the transition from shortstop to third base, because his natural position was occupied by Derek Jeter. Looking back at the Yankees from 2004-2015, where would the Yankees be at the end of each season if instead of Rodriguez they had a replacement level or average third baseman?
2004 Season:
In 2004, the Yankees finished with a record of 101-61, just three games ahead of their division rivals the Boston Red Sox. In the same season, A-Rod had a WAR of 7.6 and a WAA of 5.2, meaning he was 7.6 wins above a replacement third baseman and 5.2 wins above the average player in 2004. Without Alex Rodriguez in 2004 it is safe to say the Yankees would have won between 94 and 96 games, notching them a Wild Card spot rather than the division.
2005 Season:
The Yankees and Red Sox finished the 2005 season tied with 95 wins each, but the Yankees were awarded the division because they won the season series. 2005 was Rodriguez's best season with the Yankees, other than 2007, with a WAR of 9.4 and a WAA of 6.9. With a replacement level or average third baseman the Yankees would have won just 86-88 games, less than the 93 games the Cleveland Indians won, the Yankees would have missed the playoffs.
2006 Season:
In 2006, the Yankees won the division by 10 games ahead of the Toronto Blue Jays with 97 wins. 2006 was a down year for A-Rod, producing some of the weakest numbers of his career. Rodriguez had a WAR of 4.5 and a WAA of 2.6 in 2006. The Yankees would have won about 92-94 games without him, and probably win the division.
2007 Season:
2007 was arguably the best season Rodriguez had with the Yankees, accumulating a WAR of 9.4 and a WAA of 7.0. The Yankees only won the Wild Card in 2007 finishing with 94 wins, two games behind the Red Sox. With a replacement level or average third baseman the Yankees would have finished in the 84 to 87 win range, making it close for the Wild Card, because both the Detroit Tigers and Seattle Mariners finished with 88 wins.
2008 Season:
The Yankees failed to make the playoffs in 2008 with just 89 wins on the season. The Tampa Bay Rays and Red Sox finished ahead of the Yankees with 97 and 95 wins respectively. Rodriguez finished the season with a WAR of 6.8 and WAA of 4.7. The problem in 2008 definitely was not A-Rod, the Yankees would have finished with between 82 and 84 wins, without him.
2009 Season:
The Yankees signed some big free agents before the 2009 season and it paid off by winning 103 games and the division. A-Rod did not have a regular season as great as the rest of his career, earning a WAR of 4.1 and a WAA of 2.3, but he performed to excellence in the playoffs, helping the Yankees win the World Series. Without Rodriguez in 2009 the Yankees would have won between 99 and 101 games, still taking the division, but it would be difficult to say if they would have still won the World Series.
2010 Season:
At this point in his career Rodriguez is performing just 2.0 WAA and 4.1 WAR, not really worth the large sums of money he is being paid. In 2010 the Yankees won 95 games and a Wild Card birth, just one game behind the Rays. With a replacement level or average third baseman the Yankees would have likely still made the playoffs with 91-93 wins. The Red Sox were next in line for the Wild Card with 89 wins.
2011 Season:
The Yankees finished 2011 with the best record in the American League at 97-65. In the last All-Star year of his career, Rodriguez had a WAR of 3.9 and a WAA of 2.4. Without Rodriguez the Yankees might have finished with 93-95 wins, still winning the division ahead of the Rays, who won 91 games.
2012 Season:
The Yankees narrowly won the division with 95 wins, just two games ahead of the Baltimore Orioles. In 2012 the Yankees did not get much help from Rodriguez. He produced statistics that were practically league average with a WAR of 2.2 and a WAA of 0.3. The Yankees would have won between 93 and 95 without A-Rod in 2012. An average player would have probably yielded the same result, but a replacement level player would have made the division very close.
2013 Season:
At this point everyone thought that A-Rod's career was over. He only played 44 games because of injury and for the first time since 1995 he produced below average with a WAA of -0.3 and a WAR of 0.3. The Yankees missed the playoffs in 2013 winning just 85 games. An average or replacement level third baseman would have yielded the similar result.
2014 Season:
Alex Rodriguez was suspended for the entire 2014 season due to his use of PEDs and did not play a single game. Also, for the first time since 1993 the Yankees failed to make the playoffs in back-to-back seasons.
2015 Season:
The Yankees still have 52 games to play in this season and Alex Rodriguez is no longer the third baseman. A-Rod has assumed the role of full-time designated hitter and has found much success. This season he has a WAR of 3.1 and a WAA of 1.5. The Yankees are just 1.5 games ahead of the Toronto Blue Jays after being swept this past weekend. If the Yankees had an average or replacement level DH, it would be likely that they wouldn't be in first place.
Alex Rodriguez has had a great career with the Yankees despite the controversy about his usage of performance enhancing drugs. For many of the seasons discussed above, it is difficult to say exactly where the Yankees would have ended up. The Yankees would have fewer wins with the subtraction of Rodriguez, but the games that the Yankees did not win have to be won by another team, those can be teams within the division or outside the division. The only thing that can be said conclusively is Alex Rodriguez made the Yankees significantly better during his 11 seasons.