Jon LesterBOSTON — Jon Lester is tackling this season like a boss.

Lester has been forced to deal with extra noise since the beginning of spring training because of his impending free agency. Not only has it not impeded his performance — he’s having his best season yet — but the Red Sox ace also has set the standard for how to approach a contract year both on and off the field.

“I think he’s been a model for others to witness as players get to that stage of his career,” Red Sox manager John Farrell said Sunday after another dazzling effort by his No. 1 starter. “He’s been able to handle it in a professional manner. He’s been very, I think, forthright in not wanting it to be a distraction to his teammates or us as a team. And he’s been able to go out and maintain that high level of focus.”

Lester’s next contract understandably will remain a talking point until he ultimately inks a new deal, whether it be with Boston or another organization. Amazingly, however, Lester has been able to diffuse all potentially distracting reports while simultaneously dominating for the better part of 2014. In fact, he has gotten better as the year has progressed and the noise has increased.

“For those who see Jon the days in between starts as much as the day he takes the mound, it’s a very driven, very focused person,” Farrell said. “I’m not surprised by the way he’s handled this.”

Lester tossed eight shutout innings against the Kansas City Royals on Sunday to give the Red Sox their seventh win in eight games. The left-hander, who struck out eight while surrendering only four hits, has allowed just one earned run over his last 31 innings pitched, good for a 0.29 ERA in that stretch.

Lester, who is 10-7 with a 2.50 ERA in 20 starts overall, has allowed two earned runs or less in each of his last seven outings, matching a career-long streak for the second time. He has gone 4-0 with a 0.85 ERA (five earned runs over 52 2/3 innings) in those seven starts.

“I’ve always known Jon to be a very confident pitcher,” Farrell said. “As he’s advanced in his career, he’s certainly more understanding of what his strengths are as a pitcher. The rapport that he and (catcher) David Ross continue to rely on is present each time they take the field.”

Lester’s numbers are impressive, especially recently, regardless of all other factors. They’re downright staggering when you consider the extra questions, the increased hassle and the added pressure the nine-year veteran has faced because of his uncertain future. It truly is a testament to Lester’s leadership and poise.

“I just try to make sure I go out there and pitch well for these guys,” Lester said Sunday after securing the sixth double-digit-win season of his career. “If these guys are happy with what I’m throwing and how I’m going about my business, that’s all I care about. Like I said in the past, the other stuff will take care of itself.”

When the other stuff takes care of itself, Lester will be rewarded handsomely. He sure deserves it.