© 2014 MLB Advanced Media, L.P. All rights reserved.

6/21/2014 4:51 P.M. ET

Hefner gradually increasing intensity of rehab

MIAMI -- Among the rehabbing players visiting the Mets this weekend was right-hander Jeremy Hefner, who's been working his way back from Tommy John surgery in Port St. Lucie, Fla.

Hefner, who underwent the procedure in late August, is scheduled to throw his fourth bullpen session on Sunday. He will introduce breaking balls for the first time and also increase the intensity of his fastballs, to around 90 percent.

"I can throw as hard as I want and it doesn't hurt, which hasn't happened in a long time," Hefner said. "I'm interested to see going forward, as I increase the quantity of pitches, how my arm responds. I think it will respond very well."

Hefner started throwing on flat ground about six weeks ago. His return to the mound has been gradual. His first three bullpens were from the mound at a shorter distance than usual, with the catcher set up in front of the plate.

Armed with a new ligament, Hefner isn't nervous about pushing himself. Even though he thinks he's about six to eight weeks away from throwing a full game, his goal to join the Mets by the end of the season hasn't changed.

"If there's a need here and they want me here, I could do that," he said. "Ultimately, it's not my call."

Collins anticipates rules change for plate plays

MIAMI -- Not even a good night's sleep could stop manager Terry Collins from being frustrated with a pair of plays at the plate in Friday's 3-2 loss to the Marlins at Marlins Park.

Collins spent more than 20 minutes before Saturday's game discussing the umpires' decisions with the media. He hasn't heard from the league about it -- nor does he expect to -- but he does expect the rules to be looked at during the All-Star break and changed for 2015.

Collins said he's heard that the plate-blocking rule could morph into one that requires baserunners to slide into home on plays and prohibits catchers from going all the way to the ground to prevent access.

The Mets' issue with the calls isn't about Marcell Ozuna's throws. In both instances -- David Wright in the eighth and Kirk Nieuwenhuis to end the game -- the runners were thrown out by a clear margin. The confusion stems from the way the plate was blocked by catcher Jarrod Saltalamacchia.

Collins insists that there wasn't enough of the plate open for scoring in either play.

In the play on Wright, who was trying to score the game-tying run on a single, Collins noticed in an overhead replay that Wright had just a small lane in which he could score, and the lane was in foul territory.

"In retrospect, if you look at that, yeah [he has a lane], but he's got to slide way out to get to it," Collins said.

Worth noting

• On Saturday, in his second rehab game, outfielder Juan Lagares (strained right intercostal) played nine innings with the Gulf Coast League Mets and went 0-for-4.

• Travis d'Arnaud had three more hits on Friday for Triple-A Las Vegas, for his second straight three-hit game. d'Arnaud is hitting .458 with six doubles, six homers and 15 RBIs in 12 games for the 51s.

Maria Torres is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.