3 Takeaways from the Mariners' April atop the AL West

Takeaway #1- The starting rotation could be the best in the American League

8-1 with a 1.22 ERA in their last 12 starts as part of a historic run. They also have an insane 10.46 K/9 in that range, which is a difficult number for an individual to attain but almost impossible for five guys to accomplish together. Seattle's rotation had a slow start, with guys like Luis Castillo and George Kirby struggling in their first few starts, but they've been dominating since.

Opposing batters are hitting .163 against Luis's slider this year, and they're striking out at a 43.2% clip against the pitch. Last year, his four-seam was dominant and his sinker also performed well, but his four-seam is down almost a mile per hour this year to 95.3 MPH. Kirby's ground ball rate is down to 33% from 44.2%, which could play a role in the rise of his BABIP. His historically good command has persisted, however, with a 3% BB rate in April.

Bryce Miller and Logan Gilbert both have ERA's under 2.10, and all signs point to this unit being the strongest piece of this Mariners club. Bryce's new addition to his repertoire, his splitter, has performed with a .156 BA in April. Gilbert’s K rate is up to 29.3%, which is encouraging despite the 10.3% barrel rate. Both of these guys have actually gotten hit hard this year at points but pitched well overall. This unit has put together quality start after quality start, even Emerson Hancock has had his moments. This rotation has masked the weaknesses of the offense, which hit .217 in April and ranked in the bottom third of the MLB in wRC+.