Here's Why Lance McCullers Is 2017's Breakout Pitching Star

In his first two seasons, McCullers showed the ability to rack up strikeouts while posting some gaudy batted-ball numbers. This year, he's kept getting whiffs and inducing grounders while cutting down on walks, making him one of the game's top hurlers.

Sometimes in baseball, Jason Vargas gets really good or R.A. Dickey wins a Cy Young -- that is to say, breakouts happen out of nowhere.

Other times, we can see it coming.

Lance McCullers falls into the latter category.

There are a few things we look for when trying to identify elite-level pitchers.

Most importantly, we want a guy who gets strikeouts while limiting walks. If he can do those two things, he's firmly on our radar. If, in addition, if he can limit hard contact while generating a ton of ground balls, then we've got ourselves the makings of an upper-echelon hurler.

McCullers has shown the ability to check more than a few boxes in the past, previously posting an elite strikeout rate with mouth-watering batted-ball numbers. But he's taken his game to a new level this season, cutting down on walks -- his one bugaboo -- while continuing his stellar performance everywhere else.

It all adds up to McCullers becoming one of the game's best pitchers.

Teasing Us

The Houston Astros' righty debuted in 2015, displaying enticing upside in 125 2/3 frames. He finished his rookie campaign with a 24.8% strikeout rate, 8.3% walk rate and 3.57 SIERA. For reference, the league averages in 2015 were a 20.4% strikeout rate, 7.7% walk rate and 3.89 SIERA, so McCullers' numbers are pretty sweet for any pitcher...and he was only 21.

McCullers upped his game in certain areas in 2016, but took a step back in other facets. Overall, he pitched to a 30.1% strikeout rate, 12.8% walk rate and 3.68 SIERA in 81 innings. He was once again markedly better than a league-average pitcher (with the exception of walks) as the averages that season were a 21.1% strikeout rate, 8.2% walk rate and 4.11 SIERA.

McCuller threw ball four too often in 2016, but his batted-ball profile was dope -- he racked up a 57.3% ground-ball rate (GB%) with a 25.6% hard-hit rate -- and his 13.0% swinging-strike rate (SwStr%) fully justified his jump in strikeouts. The 2016 league averages in hard-hit rate allowed (31.4%) and ground-ball rate (44.7%) were miles off McCullers' marks.

In easily-digestible form, here's what McCullers did in his first two seasons.

Year Strikeout Rate SwStr% Walk Rate GB% Hard-Hit Rate SIERA
2015 24.8% 9.8% 8.3% 46.5% 28.9% 3.57
2016 30.1% 13.0% 12.8% 57.3% 25.4% 3.68

All in all, we had a youngster with a proven ability to get punchouts, who also possessed a superb ground-ball rate. Even with the higher-than-we'd-like walk rate, McCullers was a very good pitcher, but limiting those free passes was the final piece of the puzzle.

Mission Complete

Well, that puzzle is done finished.

Through 54 1/3 innings this season, McCullers is sporting a sparkling 6.8% walk rate. And he's maintained his excellent numbers elsewhere -- putting up a 27.2% strikeout rate, 12.1% swinging-strike rate, 60.6% ground-ball rate and 22.5% soft-hit rate and 2.94 SIERA. The ground-ball rate, soft-hit rate allowed and SIERA are all career-best clips.

In nine starts in 2017, McCullers already has two outings of no walks and at least seven innings pitched. He didn't have a single walk-free outing in 14 starts last season.

In basically all the stats that matter -- read: things a pitcher can control -- McCullers ranks among the best in the game. His ground-ball rate and SIERA each check in fourth among qualified starters. His strikeout rate sits 14th, and the soft-hit rate is 16th.

This may not be an ideal comparison here, but blind comparisons are really fun so let's have at it.

Pitcher Strikeout Rate SwStr% Walk Rate GB% Soft-Hit Rate SIERA
Player A 32.2% 15.1% 6.8% 33.1% 19.9% 2.98
Player B 26.1% 11.5% 3.4% 47.9% 25.6% 3.08
McCullers 27.2% 12.1% 6.8% 60.6% 22.5% 2.94

McCullers' numbers from this season match up well with the 2017 marks of these two pitchers, both of whom are among the best baseball has to offer. Player A is Max Scherzer, a two-time Cy Young winner, and Player B is Clayton Kershaw, who has won three Cy Young awards and is the game's best pitcher.

Of course, it's halfway through the first half of the season, so the sample size isn't huge, but McCullers has been pitching like a top-shelf ace.

Moving Forward

Everything about McCullers checks out. His traditional stats -- 4-1 record with a 2.65 ERA -- look great, and his peripherals are just as pristine. Looking at his career as a whole, he owns a 27.0% strikeout rate, 9.4% walk rate and 3.54 SIERA across 261 innings.

Oh, and this is his age-23 season.

The only question mark is health. His choice of profession -- throwing many, many baseballs each year -- makes him an injury risk, and McCullers missed all of the second half of the 2016 season with an elbow injury.

But as he performance in 2017 shows, he's healthy. Just ask Delino DeShields Jr.

Prior to this season, McCullers was a promising young guy who was already really good, but he was a decrease in walks away from becoming a bonafide ace. Now, he's cut down on the free passes, and he's performing like an elite pitcher.

His breakout coupled with Dallas Keuchel's return to form are two of the big reasons Houston is off to such a dominant start. Their 30-15 record is tops in the game, and we give them baseball-leading odds to make the playoffs (97.3%), win their division (92.9%) and capture a World Series title (17.3%).