Barring a highly-unforeseen move, the Toronto Blue Jays have reached a point in their off-season where they are adding complementary players rather than core pieces.

Even if the left-field situation remains in flux to some degree, the starting lineup can be penciled in with players currently on the roster. The same can be said for the rotation, and the team recently made a flurry of minor-league signings to ensure there is depth should they experience injury troubles.

Where the Blue Jays’ major question marks reside is in the bullpen. The back end is solid with Roberto Osuna, Aaron Sanchez and Brett Cecil, but beyond that it’s easy to poke holes.

The only other pitcher who seems sure to make the team is Aaron Loup, who comes off a career-worst year but has a track record of success. Other internal options like Ryan Tepera, Bo Schultz and Rule 5 pick Joe Biagini are likely to experience heavy competition with any newcomers brought in through free agency or on waivers.

As it stands it’s easy to see the unit as high on uncertainty and low on dependable contributors. However, that perception changes significantly if Loup can return to the form that made him so solid in the past. While the southpaw carried an ugly 4.46 ERA last season, a deeper look into his numbers suggests he’s likely to be just fine.

In most statistical categories he was as good or better in 2015 than he was in the previous two seasons.

Time Period K/9 BB/9 HR/9 K/BB Ground Ball % ERA FIP xFIP 2013-14 7.11 2.80 0.59 2.53 57.2% 2.80 3.58 3.61 2015 9.78 1.49 1.28 6.57 55.2% 4.46 3.72 2.89

Loup struck out significantly more batters, walked about half as many and kept his ground ball rate stable. Usually that’s a pretty good formula for success.

However, there were two things that led to the left-hander’s inflated ERA: an usual amount of home runs and bad luck on balls in play.

Blame for home runs allowed falls squarely on the pitcher because (with the exception of Jose Canseco) fielders don’t normally play a role in balls flying over the fence. Even so, some luck is involved. Last season 20.7 percent of fly balls left the yard against Loup compared to a league average of 11.4 percent and a career average of 7.6 percent.

Since 2002, when FanGraphs began collecting batted ball data, no pitcher qualifying for the ERA title has ever allowed more than 20 percent of fly balls to go for home runs. Unless Loup suddenly became vulnerable against the home run in a virtually unprecedented way last year, his troubles are better explained by the randomness that can occur in a 42.1 inning sample.

The other primary issue for Loup was that he allowed a .339 batting average on balls in play, once again well above league and career averages. BABIP is often dismissed as pure luck, but it is heavily influenced by changes in the batted ball types a pitcher allows. That being said, in Loup’s case there was not a major shift in the composition of the hits he allowed.

Time Period Line Drive% Ground Ball% Fly Ball% Soft-Hit% Medium-Hit% Hard-Hit% 2013-14 18.7% 57.2% 24.1% 18.8% 55.2% 26.0% 2015 21.6% 55.2% 23.2% 22.0% 52.0% 26.0%

Loup allowed a few more line drives, but it didn’t actually manifest in him getting hit harder. Realistically, the differences here are too small to be worth parsing; opposing hitters made the same kind of contact in 2015 as always.

The left-hander now knows first-hand that good process is no guarantee of great results, especially in a small sample. He threw strikes and kept the ball on the ground, but for the first time in his MLB career bad things happened regardless. Even a career-best average velocity of 93.2 mph and the ability to miss more bats than ever couldn’t save him from more balls falling in than usual and a few costly home runs.

The smart bet is on Loup having a bounce-back season in 2016. If he can keep the added juice on his fastball and resulting whiffs he might even surpass his career averages.

For a team with a bullpen that is very thin as currently constructed that’s good news. If Loup can be trusted, the Blue Jays have more than half their relief core built. Finding three middle relievers is far easier said than done, but it’s undoubtedly easier than having to find four.