Starting pitching was supposed to be a strength for the Blue Jays in 2017. We knew with the aging core and the departure of Edwin Encarnacion that the offence would continue its regression, but the team appeared to boast one of, if not the best starting rotations in the American League.

Heading into 2018, starting pitching is somewhat of a conundrum for the Blue Jays. While the rotation boasts largely the same personnel that garnered optimism prior to last season, what transpired in 2017 leaves us with more questions than answers.

Like I said, the rotation appeared to be the team’s biggest strength heading into last season. Aaron Sanchez was coming off a season in which he led American league starters in ERA, Marcus Stroman’s peripherals suggested he could be bound for a breakout, J.A. Happ had been a finalist for the Cy Young, Marco Estrada had been an All-Star, and Francisco Liriano was a wild card with major upside who seemed to figure things out after moving from Pittsburgh to Toronto.

That looked like a really damn good starting five. But it’s baseball. Things don’t just work out the way you planned because it makes sense on paper. Toronto’s rotation — and season, really — was ultimately derailed by injuries and some disappointing performances.

Sanchez said he was dealing with a blister at the end of spring training. It didn’t seem like a big deal at the time, but it ultimately ruined his entire season. Sanchez came on and off the disabled list multiple times before being shut down for the final couple months of the season. He made eight starts and pitched only 36 innings.

Stroman had the breakout season we all hoped for. He was excellent and really was Toronto’s only constant all season, working 201 innings over 33 starts and posting a 3.09 ERA. Only six times did Stroman fail to reach five innings, and in two of those starts he left the game with an injury. There aren’t enough words to describe just how excellent Stroman was in the middle of a catastrophe.

Estrada was named the Opening Day starter and looked the part for the first few months of the season. But in June and July, the soft-tosser completely imploded, putting up a period of struggle we hadn’t seen since he joined the team in 2015. He ended up having a decent finish to the season and posted a 4.98 ERA over 33 starts and 186 innings. The Jays didn’t deal Estrada at the trade deadline and signed him to a one-year extension in September.

Happ suffered an injury during his third start and went on the disabled list until the end of May. When he returned, Happ was largely the reliable top-of-the-rotation veteran starter that he was for the team in 2016. He finished the season with a 3.53 ERA over 25 starts and 145 1/3 innings.

Liriano was all over the grid last season. He had a Jekyll and Hyde situation going on, but it seemed that we saw way more bad from good from the lefty. He also got injured in May and missed and handful of starts. The Jays dealt Liriano at the trade deadline to the Astros and he finished his season with a terrible 5.88 ERA over 18 starts and 82 2/3 innings with the Blue Jays.

Thanks to those injuries, the Jays ended up using 14 different starting pitchers over the course of the season. While some showed flashes of brilliance, they were largely very, very bad. The Jays plowed through Mat Latos, Casey Lawrence, Mike Bolsinger, Cesar Valdez, Nick Tepesch, Brett Anderson, Tom Koehler, Joe Biagini, and Chris Rowley and weren’t able to find anyone to consistently fill the void left by Sanchez and Liriano.

The first few aren’t worthing talking about because holy shit I want to erase a lot of those starts from my memory none of them are in the team’s plans. But the rest of the group? Anderson might have played his way into a contract, Koehler was used as a reliever and could have a future in that role, and Biagini and Rowley showed some pretty solid flashes for guys who weren’t expected to be thrown into the fire.

Biagini made 18 starts, tied with Liriano for the fifth-most on the team. He was expected to be a multi-inning reliever, the role he was so successful in during his excellent 2016 rookie campaign, but was thrown into the rotation amidst injuries. He got off to a really good start but predictably burned out and struggled as time went on. He went down to Triple-A to sort himself out and came back up and finished the season in the rotation, showing signs of excellence at times while looking terrible other times. It was a rollercoaster.

Rowley came out of nowhere, becoming the first West Point Military grad to make a Major league start. It was a great story for a guy who wasn’t drafted, and he put up a few good starts in August before getting put in the bullpen in September. Couple Rowley’s solid showing with his excellent season in Double- and Triple-A and you actually have a prospect here.

All told, according to FanGraphs, the Blue Jays starting pitchers posted a 12.7 WAR as a group, good for sixth in the American League. That’s honestly pretty impressive considering the revolving door of minor leaguers, random computer generated names, and journeymen that took the hill for the team last season.

It’s interesting to think what could have been if not for that blister. I know it isn’t as simple as this, but if you take 33 starts by, like, Latos, Lawrence, Valdez, Tepesch, and Biagini and replace them with what you’d expect from a healthy Aaron Sanchez, you’re adding quite a few wins by replacement. Not only is Sanchez vastly better than those starters, you save the bullpen a lot of energy not having to mop up the messes left by guys who couldn’t clear five innings with any sort of consistency.

Does that mean we should view the rotation as a strength heading into next season? That’s a difficult question answer because we still have no idea what to expect from Sanchez. If the blister goes away and he puts up another All-Star season, yeah, this is a very good rotation. If not? Ehhh.

As of right now, the Jays have Stroman, Estrada, Happ, and Sanchez pencilled in as four of their five starters. The fifth starter is up in the air. Maybe it’s Brett Anderson, who was solid in his September showing. Maybe it’s Biagini who actually gets stretched out in spring training. Maybe it’s a free agent or trade acquisition. Really, hopefully it’s a trade or free agent acquisition.

But you also have to consider Sanchez a question mark, because his health simply isn’t a sure thing. This blister thing has evolved from just a weird red sore on his finger that goofs up his grips and makes it impossible to throw properly for a few weeks. This has become a pretty serious issue involving damage to the ligaments in his finger and it could certainly flare up again in 2018.

The important thing for the Blue Jays regarding starting pitching heading into 2018 is depth. That was a massive issue last season. In 2016, the team went through the year using only six seven starters — Sanchez, Stroman, Estrada, Happ, Liriano, R.A. Dickey, and Drew Hutchison who I completely forgot about — and the only drama they had to navigate was whether or not to shut down Sanchez as he reached his innings limit.

Of course, based on how smoothly 2016 went and how solid that rotation seemed, having strong fallback nets didn’t seem like a big issue. That’s obviously different after 2017 with the question marks attached to Sanchez and with Liriano out of the picture. Some depth will come internally. It’s sensible to start Biagini in Triple-A while Rowley and Borucki are developing, available options in the minors.

The free agent market boasts a few marquee names like Jake Arrieta and Yu Darvish that would obviously make this rotation very good. But knowing this front office and ownership, the team won’t be in on those expensive players. We’re much more likely to see them acquire a cheaper, controllable asset via trade or a make more low-key Happ-esque signing like Jason Vargas or Alex Cobb.

Regardless, the Jays need another legitimate starting pitcher to add to their rotation because you really don’t want Biagini and Rowley to be your first call up options after, say, Sanchez and, like, Brett Anderson, who are two of your starting five, go on the disabled list in April. Then all of a sudden you’re right back where you were last year, grabbing scrubs from the waivers wire and random fans from the audience to make starts. I would hope the front office doesn’t view this rotation as four sure things in need of a fifth guy and instead endeavours to acquire a middle-of-the-rotation type to push everyone down a spot. Because then you can navigate through *gulp* another season in which Sanchez struggles with the blister.

On paper, it seems like you can count on Stroman, Estrada, Happ, and Sanchez to be the beginning of a very good starting rotation. But if we’ve learned our lesson from last season, don’t count on anything to be a sure thing.