Since his near-month-long stint on the injured list with a right hamstring strain, Senga hasn't been the same. On Tuesday, Mets president of baseball operations David Stearns provided the organization's reasons why.
"I don't think we've seen the consistent quality of stuff in the zone. And when you don't have the consistent quality of stuff in the zone, you tend to nibble a little bit more. ... I think he's done a really nice job of minimizing damage -- we've had a lot of traffic in his starts, but he's generally kept us in the game and been competitive."
In his first 13 starts, Senga posted a 1.47 ERA with 70 strikeouts, allowing just four home runs in 108 2/3 innings. However, in eight starts since returning from the IL, he has a 5.40 ERA with 33 strikeouts and seven home runs allowed in just 35 innings.
Senga has labored in his starts since coming off the IL. Where he averaged 5 2/3 innings per start before his IL stint, he's reached that mark just once since then.
"He's frustrated. He doesn't think he's pitching at his best right now," Stearns said. "So we're going to continue to work with him and do our best to get him to a good spot."
In Monday's 13-3 win against the Philadelphia Phillies, Senga's final line failed to tell the full story. While he only allowed three runs in four innings, he stranded six runners.
This occurred in a start where he was on regular, four days' rest. But Senga prefers five, essentially forcing the Mets to make a roster decision they might otherwise have waited to make.
On Tuesday, the Mets announced that Jonah Tong, their No. 3 prospect (Baseball America), would be making his MLB debut against the Miami Marlins on Friday at Citi Field. This will allow the club to send Senga back to the mound on five days' rest.
"I'm going to be honest, performance matters," Mets manager Carlos Mendoza said. "We're to a point now where we've got to see performance, and that was a conversation with him. We need him because he's an ace; we've seen it in the past, but we haven't been able to get that consistency.
"Maybe it's the regular rest, the extra day. Whatever it is, we're getting to a point where every game we've got to put our best guys out there."
While the sample size is limited, especially in starts where Senga gets four days' rest, the difference is dramatic. In 34 career starts on five days' rest, Senga has a 2.70 ERA versus a 5.09 ERA in four starts on four day's rest.
The addition of Tong all but assures that Senga will pitch on his preferred day, at least in the regular season.
What about the postseason?
"I'm not going to say no (to sending Senga out on regular rest)," Mendoza said, "because you never know what happens."