NEW YORK -- Neil Walker said he was in relatively little pain as he limped into the Mets' news conference room on Thursday afternoon, a compression sleeve wrapped around his left leg. But the reality was clear: Walker, who tumbled to the ground trying to leg out a bunt single on Wednesday, will miss a significant portion of the season.
An MRI taken Thursday on Walker's leg revealed a partially torn left hamstring. He received a platelet-rich plasma injection and the Mets recalled Gavin Cecchini -- not No. 1 prospect Amed Rosario -- to replace him, though T.J. Rivera will become the team's everyday second baseman in Walker's absence. The Mets expect that arrangement to last "several weeks." Cecchini hit .249/.313/.349 with three homers in 62 games at Triple-A Las Vegas.
"If we're looking at a month, I feel pretty confident that I'll be right back in the swing of things when I come back," said Walker, who was batting .319 with seven homers and a .973 OPS since the start of May. "There's no good time for an injury. So I'm going to do everything I can to get back as quickly as I can."

Walker's absence robbed the Mets of one of their most productive hitters. It also presented them with a clear opportunity to promote Rosario, a shortstop batting .333 with seven home runs and an .870 OPS in 64 games at Las Vegas. Asked multiple times about Rosario on Thursday, Mets general manager Sandy Alderson pointed to two primary reasons why the team did not recall him.
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The first is that, in Alderson's estimation, "We have some good players here." Without Walker and Asdrubal Cabrera, who is also on the disabled list, the Mets will proceed with a starting infield of Lucas Duda, Rivera, Jose Reyes and Wilmer Flores. And while Reyes was batting just .187 in 61 games entering Thursday, Alderson only went as far as to call the Mets' overall shortstop play "inconsistent."
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"Look, I don't want this to become a debate over … Amed Rosario," Alderson said. "We've seen some great plays made. We've seen some plays made poorly. The question is whether changes would make us better, and if they don't, what happens after that. So right now, we're comfortable with where we are."

The second reason behind the Mets' hesitancy to call up Rosario is their uncertainty over whether he is ready to thrive in the Majors. For most of the season, the assumption was that Rosario would become a more viable promotion candidate once MLB's Super Two arbitration cutoff passed, potentially saving the club millions of dollars. With that date in the past, the organization's decision now revolves strictly around Rosario's baseball acumen.
"This is about winning," Alderson said. "We're not talking about Super Two status -- that's gone, that's past. We're not talking about any of those issues. We're talking about the team on the field primarily, and whether we are a better team with what we have or bringing someone else in. That calculation may change over the next week or 10 days. We'll see. But today, we're comfortable with what we have."
Added Alderson: "Sort of an overriding desire on our part is that when [Rosario] comes up, he never goes back."