PITTSFORD, N.Y. — Don’t call Frank Gore old. He is old-school, though.

From his training habits to his playing style, the Buffalo Bills‘ 36-year-old running back’s mentality is of a different era — show up, do your job and do it well. No flash, all substance. Because in the NFL, there’s always someone waiting in line for your spot; you don’t get long to show why you deserve it.

“If you’re going to be a baller, that second year [of your career] you should see it,” Gore said. “But you’ve got to work at it, you’ve got to love what you do. Once you do that, you can tell who’s really taking it seriously.”

By his definition, Gore proved his value during a 1,695-yard, eight-touchdown campaign in his second season in 2006. But players don’t progress at the same rate. Often in their first two seasons, they figure the league out and it figures them out — whether that means a strong rookie season before a regression in Year 2, or a pedestrian first year before a resurgent second season.

That’s why Year 3 is so critical in a player’s development.

In the Bills’ case, the team’s third-year players carry a heavier-than-average burden. Cornerback Tre’Davious White, left tackle Dion Dawkins, receiver Zay Jones and linebacker Matt Milano represent coach Sean McDermott’s first draft class.

“It used to be, give a player two years and show him who he is,” McDermott said. “But now with some of the time constraints that we have through the entire calendar year, you know, you want to make sure you give a player enough time — in this case that third year is important.

“Sometimes if you watch the ebbs and flows of careers, first year might be ‘X’, the next year it changes a little bit, either up or down and then that third year, you kind of find the true player — and that’s really what we are looking for for those players.”

Buffalo’s third-year players have each had ups and downs over the past two seasons. White and Dawkins started 16 and 11 games in 2017, respectively, finishing as two of the top rookies in their class. But both struggled at times in 2018 once opponents had a full season’s worth of tape to study. White committed 11 penalties last season compared to three as a rookie, and Dawkins was flagged 14 times, compared to four times as a rookie.

At two of the sport’s premium positions and with contract extensions on the horizon, White and Dawkins can show which year was the anomaly. For White, that preparation means practicing with oversized oven mitts to reduce his defensive holding calls. For Dawkins, it involves self-evaluating as the anchor of a rebuilt offensive line.

“[Dawkins] looks very focused at this point and I would say going back to the spring,” McDermott said. “I don’t want to say he was a different guy or a new guy, but he looks very focused and seems to be playing with a little bit more decisiveness at this point.”

Milano and Jones, on the other hand, broke out in their second seasons — especially Milano, who played 90 percent of Buffalo’s defensive snaps before breaking his fibula in the team’s 13th game.

He’s back on the field in 2019, as is the Bills’ leading returning receiver, Jones. A second-round pick in 2017, Jones more than doubled his catches, receiving yards and touchdowns from his rookie campaign — during which he said finding consistency was his biggest challenge.

“When you come into the league, it can expose your flaws,” Jones said. “I was put in a position where I was a No. 1 [receiver] right away. A lot was placed on me, and I handled it to the best of my ability. I had my highs, but I definitely had my lows. Just finding a consistent ground of keeping an even keel — not getting too high and not getting too low.”

The Bills added proven veterans Cole Beasley and John Brown this past offseason, easing the load Jones carried during his first two seasons.

Along with Milano, White and Dawkins, Buffalo needs Jones to transition from promising draft pick to franchise cornerstone. This season will reveal if those expectations are realistic.

“Going into my second year, I got a little more rest and got my feet under me a little bit,” Jones said. “Understood the pace of the game and the process of visualization — how it’s going to be, what am I going to go through and experience.

“I intend to stay on that trend. Hopefully, our team stays in that trend of constantly progressing, but the game slows down as you get older. As you get more experience, things become more comfortable — but the game will teach you something if you’re not ready.”