ST. PETERSBURG — Derek Shelton knew he was going to get fired from his job as Rays hitting coach at some point. There had been enough scrutiny, enough slumps and skids during his seven-year run that there were several junctures when he wouldn't have been shocked to get that call.But Tuesday morning, with a month left in the season, and with the offense on a marked recent upswing?"The timing of it was surprising," Shelton said.In naming minor-league hitting coordinator Chad Mottola to take over, starting Thursday in New York and through at least next season, the Rays said their primary objective was to find a "new voice" who could connect better with the players.Doing so raised some eyebrows in the clubhouse, with veteran leader Evan Longoria saying he was caught off guard by the move and felt Shelton had done a "great" job, Kevin Kiermaier among those refusing to say anything and the group gathering in the batting cage for an impromptu session to hear what manager Kevin Cash would say.And it raised several questions.The biggest, of course, was why?That seemed a bit hard for Rays brass to fully explain, beyond the "new voice" mantra. Even baseball operations president Matt Silverman acknowledged "it is very difficult to measure the success of a hitting coach," or any other since it is so much more about the players.Certainly there was statistical cause, as the Rays during Shelton's 2010-16 tenure ranked 11th in the American League in runs (4,738), 13th in average (.247) and second (or 14th) in strikeouts (8,638), none of which are good.But there isn't the same correlation as an offensive coordinator in football, as Shelton doesn't call the plays. Nor, no matter how much prep work is done, does he have a speaker in their helmets telling them when to swing. And he certainly wasn't responsible for some of the not ready or not capable players they've had in the lineups as they slog through a third straight losing season.Cash and Silverman both heaped praise on Shelton for how hard he worked, how good of a rapport he had with the players, how much he knew about hitting and how well he adapted to the different assignments they gave him. They said he did nothing wrong, that they had been talking about doing this for several weeks. The Rays did go to the playoffs three times on his watch, and there were success stories to offset the hitters he failed to reach or make better.And they made it clear that this change was not being made to facilitate the installation of a new system or plan of attack. "We're not looking to revamp or overhaul anything," Cash said.But Cash hinted that Shelton's message to some players may have been getting stale, noting in that role there is "a shelf life" and "it was time" for that new voice.And Silverman said Mottola, who may be a bit broader and less technical in style than Shelton, could be a better conduit. "Seven years together with our hitters, that approach is one we've been able to get a lot out of it. Derek has changed his message as our personnel has changed, as our philosophies have changed," Silverman said."But the connections with the players, we think that there is a possibility and a hope that some of that can improve with a different person in that chair, with a different voice, different relationships, a fresh start."And, so why now?What Cash and Silverman said about giving Shelton, who was signed through 2017, more time to find a new gig was polite, but he'll be fine, accepting of the news and sure to land elsewhere.He said he didn't "know where it came from" given what he felt were "good relationships" with players and bosses, getting the same spiel about the new voice.This was all about Mottola, about giving him the time to get to know the hitters and, more importantly, for them to get comfortable with and to trust him."The last three-four (weeks) will be a good foundation for Chad to continue to build on the relationships that he already has and have something going into the offseason as he's connecting with our core group of guys," Cash said.As a minor-league coordinator, Mottola is familiar with the younger players but has had limited exposure with the big-league veterans, basically just some occasional spring training interaction. There is a lot he is going to need to learn, as much about personalities as swing planes, and he is going to need every day this move affords him.Longoria said it can take "a couple months" to develop the proper relationship. "Pretty much every guy has certain drills they like to do, certain keys that their swing goes off of," he said. "To really understand those nuances, and to really trust a guy as far as him analyzing it doesn't come quickly."Firing a coach during the season is a bit uncharacteristic for the Rays, but it fits in with the recent stretch of moves — releasing Desmond Jennings, demoting Tim Beckham — to set the tone and establish the framework for a more successful 2017.In those cases, the Rays sent a strong message. With this move, they are just changing the messenger. Marc Topkin can be reached at firstname.lastname@example.org . Follow @TBTimes_Rays.