The New York Yankees lackluster offense was on full display Tuesday night when they failed to score for 12 innings against Texas Rangers rookie pitcher Nick Martinez. Luckily, earlier that day, the Yankees acquired San Diego Padres third baseman Chase Headley to provide some more offense. Low and behold, Headley — who wasn’t even at Yankee Stadium when the game started — saved his new team with a walk-off single in the bottom of the 14th.

The Yankees, like every year, think they can make the playoffs, and joining them in that belief is 17 other teams that are within five games of a playoff spot, a level of parity baseball has not really seen in a long time.

As the non-waiver trade deadline approaches this Thursday, these teams will decide if they can add the missing pieces to get them to the playoffs or if they should stick with what they have. As the buyers and sellers sort themselves out, it would be wise for these teams to give themselves an honest assessment and understand that while some trades work out, others will not help and can’t fix a team that never really had a true shot.

The most recent example of a great move is when Indians pitcher C.C. Sabathia was traded to the Brewers on July 7, 2008. He went 11-2 with a 1.65 ERA, had seven complete games and had a 4.6 WAR, which, according to fangraphs.com, was a number only 18 pitchers had beaten that season, all of whom had the luxury of three additional months to compile their numbers. He single-handedly led the Brewers into the playoffs for the first time since 1982 and helped to energize the team’s fan base.

A recent move that didn’t really work out, though, is when the Angels traded for pitcher Zack Greinke from the Brewers in 2012 for prospects, including shortstop Jean Segura, who made the All-Star team in 2013. Greinke didn’t pitch poorly, he went 6-2 with a 3.56 ERA, but the Angels failed to make the playoffs and Greinke signed with the Dodgers after the season. Was it worth it to give up a prospect like Segura for a half-year rental, who, despite his down year this season, is still 24 and has time to prove 2013 wasn’t a fluke?

These aren’t the only instances like this. When the Phillies acquired pitcher Cliff Lee in 2009 from the Indians, he helped lead them back to the World Series and pitched dominantly in the playoffs. Despite their loss to the Yankees, the trade eventually worked out. However, when the Giants traded for Mets outfielder Carlos Beltran, they still failed to make the playoffs, and Beltran bolted for the Cardinals after the season. Meanwhile, the Giants gave up pitcher Zack Wheeler, who has the potential to be a dominant, frontline starter in the years to come.

Drawing the line between trying to win now and developing prospects for the future is always difficult. I know hindsight is 20/20, but those half-year rentals for the Angels and Giants don’t seem so great now, especially considering their farm systems are currently ranked 30th and 22nd, respectively, according to Baseball Prospectus. However, since both teams are among the best in baseball now, one could argue that the trades did not hurt either franchise too badly.

Regardless, even though 18 teams currently think they have a chance to win it all, only a few are actually good enough. As a Yankees fan, I’d especially like the team to be cautious. While I’m spoiled by its year-to-year competitiveness and admire how it always wants to give us fans a championship product, I don’t want to see the team add another veteran to a roster with too many guys already over 30 who can’t stay healthy and are owed a lot of money.

Our deals in years past  — Alfonso Soriano, Ichiro, Lance Berkman, Kerry Wood, Ivan Rodriguez — would have been great if they were made in 2004, but the team doesn’t need another aging veteran (Cliff Lee). With a 23rd-ranked farm system according to Baseball Prospectus, the Yankees should hold on to their prospects to get younger and be more competitive in years when they have a more legitimate chance to win it all.

While more than half the league is excited at the prospect of a trip to the World Series, the big trades do not always work out.

Before they ship off their young talent they should be wary of all the potential outcomes, both in the immediate and distant future.

Robert DePaolo is a junior in the College. Sideline Summer appears every other Friday at thehoya.com