Phillies right-hander Jake Arrieta has an ERA of 4.67 for the season, and over his last three starts he's allowed a total of 15 runs. In other words, Arrieta -- even allowing that his decline phase is currently in place -- hasn't been himself. After getting roughed up by the Mets on Saturday, Arrieta seemed particularly agitated. Now it seems there's an explanation. 

Here's this from Ken Rosenthal and Matt Gelb of The Athletic

Arrieta has a bone spur in his right elbow, according to a source, and it likely will require surgery to remove it -- surgery that those involved had hoped could wait until the end of the season. That delay is no longer certain. It is unclear how much the bone spur has affected Arrieta, who has a 6.63 ERA in his past seven starts.

And more: 

There are two considerations when attempting to pitch through a condition such as this one: one, whether it's possible physically, and two, whether the pitcher can perform adequately. Given recent results, the latter is very much an unknown with the 33-year-old Arrieta. 

Arrieta is coming off a first season in Philly in which he pitched to a 3.96 ERA and 2.42 K/BB ratio -- above-average as starting pitchers go but hardly the results you want from a $75 million addition. This season, he's been substantially worse. With the Phillies heavily committed to making the postseason in 2019, you have to think that Arrieta's uncertain status and near-term future increase the pressure on GM Matt Klentak to land a starting pitcher before the July 31 trade deadline.