The Pirates were 68-59 on Aug. 27 when Walker began to feel the effects of what was eventually diagnosed as a herniated disk. He missed 27 of the team's final 35 games, gritting his teeth as the Pirates faded from contention.
"There's not a more helpless feeling as a guy that's used to playing every day than to not be out there and help the team, especially in times of need," Walker said.
Replacement Brock Holt struggled to provide a spark either at the plate or in the field and Pittsburgh's offense all but disappeared without help from the steady switch-hitter determined to return the Pirates to prominence.
Walker's absence was hardly the only thing that went wrong over the season's final six weeks, though that didn't make it any easier to swallow. It's one of the reasons why the 27-year-old started his offseason program barely a week after the Pirates ended up 79-83.
Working with a team of specialists, Walker gradually rebuilt strength in his back and was assured at every step along the way it not be a recurring problem. That was welcome news to a 6-foot-3 guy who spends half of his time on the job in a defensive crouch on the edge of the infield.
A typical day now includes a 15-20 minute series of exercises designed to take some of the pressure off his back. He focuses on his core and his hips. The looser they are, the better he feels. It's not quite yoga, but it's pretty close. Getting a head start on his offseason program also helped him avoid the weight gain that tends to pop up over the winter. He arrived in Bradenton last month about 10 pounds lighter than he typically is this time of year.
"I felt great and I haven't felt any weaker or anything like that, which has been good," he said. "To not carry a little extra weight on top is probably good for my back anyway."
Though Walker hasn't exactly busted out during spring training — he's hitting .240 (6 for 25) in ten games — he's confident he can be just as productive as he was a year ago when he batted .280 with a career-high 14 homers and 69 RBI despite missing more than a month.
Those numbers were good enough for Walker to get a pay bump from $500,000 to $3.3 million, a deal he worked out with the Pirates just hours before going to arbitration.
"It can turn into a spitting match if you let it, but it wasn't that way," he said. "They submitted their numbers, we submitted ours and we met right smack in the middle."
Even so, the Pirates have yet to reach out to Walker to discuss a longer term deal even though he is considered part of the core the team wants to build around. Walker insists he's not worried about his future, pointing out that he still has three years of arbitration remaining before he becomes a free agent.
Maybe, but Pittsburgh made sure to lock up All-Star centerfielder Andrew McCutchen last spring. In a way, Walker may be almost as valuable to the franchise because of his steady production and his western Pennsylvania roots. The team promotes Walker heavily. On Mother's Day last year, every female fan that walked through the gates received a pink Walker jersey, as did every child in attendance.
Walker is diplomatic when talking about his long-term importance to the Pirates.
"The way I see it is if I prepare myself like I have during the offseason and every day I go out and give my best effort and stay healthy, all that stuff will take care of itself," he said. "When we get to that bridge, we'll cross it."
That apparently won't happen this spring. Owner Bob Nutting has stressed the team is "willing to pay up for a great player" but that the club "can't ever do it to feel like it's the popular thing that we're doing."
Walker doesn't believe his future will be a distraction. He's more anxious to help the Pirates get over the hump. That includes becoming more productive as a right-handed hitter. He hit just .246 from the right side and struggled to generate any power. All but five of his 29 hits while batting right-handed were singles and all of his home runs came from the left side.
"The hardest part of being a switch hitter is finding the happy medium," he said. "That's why you have to simplify things as much as possible. It's tough. It's not easy."
There are no plans to give up hitting right-handed and he knows he can still contribute in other ways. Walker says he learned a lot by watching Pittsburgh shortstop Clint Barmes play Gold Glove-caliber defense in 2012 despite a horrendous start at the plate, when it took Barmes two months to hit over .200.
"To see him go about his business on the defensive end has made me that much better of a defensive player," Walker said.
One whose back is ready to handle a full workload.
"From all the work that I've done this offseason, I've challenged my back to a degree above what I will during the season," he said. "It's responded well every single time."