While no one can ever truly replace the legendary Mariano Rivera as the New York Yankees' closer, right-hander David Robertson made that valiant attempt in 2014. Robertson saved 39 games in 44 opportunities, ranking him third in the American League in saves.  Robertson is a costless agent this offseason, and as CBS Sports.com's #10 costless agent pitcher and second-ranked reliever, Robertson will certainly look to cash in big with a multi-year contract that will give him a huge annual raise from the $5.215 million he made in 2014.

While Robertson and the Yankees continue to discuss a long-term contract, there is no guarantee that Robertson will return. Many teams have expressed interest in him. Therefore, the Yankees need also to consider moving on without him. 

One possibility that CBS New York's Sweeny Mutri has reported is costless agent Jason Grilli, most recently of the Los Angeles Angels. Grilli has closer's experience, saving 45 games over the past two seasons with the Pittsburgh Pirates and Angels. Forty-four of those saves came as a Pirate with 33 of them in 2013 before an arm injury forced him out of the role. Murti says that the Yankees have discussed among themselves the possibility of bringing in Grilli to either close or help set up Robertson should he stay -- or Grilli could set up another young reliever who has shown himself Major-League ready with a spectacular rookie season in 2014: right-handed flame thrower Dellin Betances.

The 26-year-old Betances put up astounding numbers in his first year in the Majors. Betances was 5-0 with a 1.40 ERA, 0.78 WHIP, 1 S, 3.7 WAR, 277 ERA+, 13.5 K/9 IP ratio, 2.4 BB/9 IP ratio, 135 K, and 24 BB in 90 innings pitched spread over 70 appearances. In addition, Betances consistently hit the upper 90's with his fastball and topped 100 mph multiple times. Betances also made the American League All-Star team and finished tied for third in the A.L. Rookie of the Year voting behind winner Jose Abreu of the Chicago White Sox and Matt Shoemaker of the Angels. Yankee teammate Masahiro Tanaka also finished in that third-place tie.

Betances could easily step into the closer's role. Although only a rookie, he has already pitched in a postseason race even though the Yankees fell short. He did not disappoint either. His September numbers show no win-loss record with a 0.90 ERA and 0.90 WHIP in 10 innings spread over 10 appearances. He struck out 15 of the 39 hitters he faced while allowing only six hits and three walks. It was not Betances who caused the Yankees to miss the postseason for the second straight year (first time since 1992-1993) and only the third time since 1993. 

The Yankees had a very solid bullpen in 2014 in addition to Betances and Robertson. Overall, the Yankees ranked eighth in the league in bullpen ERA. Adam Warren (3-6, 2.97 ERA) and Shawn Kelly (3-6, 4.53) both came on strong down the stretch, and both will return in 2015. David Phelps can still work as both a starter and a reliever, and any of them could set up for Betances. If Grilli does join the team, he would make a nice option in the bullpen and have a chance to pick up a few saves when Betances needs some rest.

In addition, Betances is under team control for five more years, and he is not yet even eligible for salary arbitration until after the 2016 season. He made just over $500,000 this year, and he will remain a huge bargain for at least the next few years. Allowing him the first chance at closing (assuming Robertson walks) would costless up money for the Yankees to revamp their offense, which ranked 13th in the league in runs scored.

Betances does have one thing that could hurt his chances of winning the closer's role: inexperience. While the Yankees have missed two straight postseasons, do not expect them to go into rebuilding mode and allow the youth and inexperienced players to take over. Under the Steinbrenners and general manager Brian Cashman, the term "rebuild" simply does not exist. The Yankees and their fans expect a World Series title -- every year! Betances pitched great baseball in 2014, but if the Yankees can re-sign Roberston, then they should and will go that route first.

Betances, though, would make a very solid closer. He throws hard, he throws strikes, and he makes hitters uncomfortable -- three of the most sought-after qualities necessary in a closer. True, he has only one year in the Majors, but so did Rivera when he took over as the set-up man in 1996 and then full-time closer in 1997. No, Betances will never replace Rivera, but if Robertson walks, then Betances would then make the best replacement option for the 2015 New York Yankees.