PIT@STL: Walker hurt trying to break up double play

NEW YORK -- Second baseman Neil Walker began his rehab assignment with Double-A Altoona on Thursday night, going 1-for-4 with a double and playing six innings in the field. Walker has been assigned to the disabled list since he lacerated his right hand sliding into second base April 26 in St. Louis. He was spiked by Cardinals shortstop Pete Kozma.

Walker is eligible to return from the DL on Sunday in the series finale at Citi Field against the Mets.

He has hit .186 with one home run and two doubles in 70 career at-bats against the Mets. If he does play Sunday, the switch-hitter will make his return against Matt Harvey.

Walker is hitting .253 (20-for-79) with two doubles, a triple and a homer this season.

Morton to throw bullpen session Friday at Citi Field

NEW YORK -- The timing of a return to active duty in the big leagues by Pirates starter Charlie Morton may become a tad clearer this weekend when the club determines how his right shoulder responds to a Friday bullpen session at Citi Field. Morton, who underwent Tommy John surgery on his right elbow in June, experienced tightness in his shoulder after a rehab start.

His elbow is apparently no longer an issue, and the Pirates are confident the shoulder tightness is not a serious malady.

"We hope to resume his rehab after his bullpen," manager Clint Hurdle said. "You just keep moving forward and deal with what you have to deal with. Charlie was alarmed by what he felt [in his shoulder], and it was proper to shut him down, but he understands it's just something he has to push through."

Martin returns behind plate after four-day hiatus

WSH@PIT: Martin makes the sliding catch on a popup

NEW YORK -- Catcher Russell Martin was back in the starting lineup Thursday after missing the Pirates' previous two games with stiffness in his neck. Martin last caught on Saturday against the Nationals. Manager Clint Hurdle gave him Sunday off behind the plate -- Martin started at third base for the second time this season -- and the Pirates were off Monday.

Martin did not play either of the Pirates' two games against the Mariners this week.

Hurdle said Martin may play some right field when needed.

Martin entered Thursday's game against the Mets with six home runs, the most of the team. His next home run will be the 100th of his career.

Rookie Welker to serve long role in bullpen

NEW YORK -- Right-hander Duke Welker, recalled from Triple-A Indianapolis on Wednesday, will serve as the Pirates' long reliever as Jeanmar Gomez fills in for the injured James McDonald in the rotation. McDonald (2-2 in six starts) last pitched May 3 and developed discomfort in his right shoulder.

Gomez (2-0 with a 2.38 ERA in 22 2/3 innings as a starter and reliever) is to start Sunday against the Mets, opposite phenom Matt Harvey (4-0 in seven starts).

Worth noting

• Hurdle on the Mets: "Every team I've managed [against in New York] has been challenged. From what I can see, they steamroll pretty well. So if you get them down, you have to keep them down."

• The Pirates had lost 12 of 15 games at Citi Field before Thursday.

• The Pirates began Thursday with a 7-4 record against teams from the National League East. Their record in road games against the NL East was 3-1.