The Yankees are at .500 and Ivan Nova is a big reason why

Ivan Nova has stabilized the back of the Yankees' rotation and has allowed the team to get to its bullpen trio more often. Al Bello/Getty Images

NEW YORK -- The New York Yankees are at .500 in large part because they traded Luis Severino's terrible starts for Ivan Nova's strong ones.

Nova, who is on the mound Wednesday night as the Yankees look for their seventh straight win, has started three games, which all were Yankees victories.

Another good start on Wednesday should cement his place in the Yankees' rotation. With 20 games in 20 days, the Yankees are toying with adding a sixth starter at some point, according to Joe Girardi, which could mean Severino's return from the DL might put him in the majors.

But Severino -- who has his first rehab start Sunday after being placed on the DL with a triceps strain -- had been awful, going 0-6 with a 7.46 ERA and pitching like one of the worst starters in baseball.

If the Yankees go for a sixth starter, they might move Richard Bleier, a 29-year-old lefty, to the 40-man and promote him for a shot over Severino. Bleier has a 2.57 ERA in five Triple-A starts, and Yankees officials have been impressed.

Meanwhile, Nova is 2-0 with a 1.65 ERA in his three starts, which has helped the Yankees rip off 14 wins out of their last 20 games. The Yankees have six straight quality starts, which allows them to properly set up their bullpen each day. By tacking on some insurance runs during Tuesday's 6-0 win over the Blue Jays, they only had to use Dellin Betances of the Big 3.

As for Nova, he appeared to be a strong sleeper candidate to have a solid season. He is a year removed from Tommy John surgery, which is typically when pitchers return to top form. He is due to be a free agent, which is often a motivator for players. His up-and-down career seemed ready to go back up after a few years down.

Nova just needed the chance. He nearly won the fifth starter spot out of spring, but instead the job was given to CC Sabathia moreso due to Sabathia's superior resume than any spring training sign that he looked very good.

As it turns out, Sabathia and Nova are combining to form a pretty good No. 4-5 combination -- really the 3-4 slots when you consider how Michael Pineda has pitched. Sabathia is 3-2 with a 3.41 ERA, while Nova is 3-1 with a 3.26 ERA.

Nathan Eovaldi and Masahiro Tanaka have combined to be a bit more consistent at the top of the rotation, which has allowed the Yankees to go to their Big 3 relievers during their winning streak.

Eovaldi (5-2) threw a six scoreless innings Tuesday as his ERA ducked just under four.

The fact the Big 3 is fully available Wednesday works perfectly for Nova, who is really a two-pitch guy these days. His fastball-curveball combination can maybe get him through orders twice, which can take him through the fifth, maybe even the sixth.

"That's all you need," Nova said. "Those three guys in the bullpen have been amazing."

In Nova's last start, Girardi took him out after six innings of one-run ball, even though he just had 62 pitches. Girardi had the Big 3 available, so he was going to use them.

The whole formula for the Yankees is predicated on being able to start well enough so they can get to their finishers. By trading in Nova for Severino, the Yankees have been able to do that more for the last few weeks.

Nova has been a big reason why the Yankees are 22-22 and possibly on the way up.