ST. LOUIS -- The friendship of Cardinals starter John Lackey and Cubs starter Jon Lester runs deep and is sure to continue well beyond Friday night. This is despite the fact that both of them have divergent goals when they meet in Game 1 of the National League Division Series at Busch Stadium, live on TBS at 5:30 p.m. CT.

Lackey and Lester became best friends when both pitched in the same rotation with the Red Sox. They won a World Series together for Boston in 2013 and remained close since they headed to separate teams.

"It's not too often you get to be in a situation like this to go against one of your better friends," Lester said. "But, come tomorrow, we're not buddies anymore."

:: NLDS: Cubs vs. Cardinals -- Tune-in info ::

They work in an extraordinary profession, and were known for pushing each other to their limits during workouts while carrying Boston's 2013 rotation through the postseason. Lester allowed one earned run over 15 1/3 innings in two World Series starts, and Lackey won the clinching Game 6 over St. Louis with one run over 6 2/3 innings.

Yet, it's the simpler things that bond Lackey and Lester.

"Country music, hunting, trucks, you know, stuff like that," Lackey said in low-key fashion on Thursday.

But make no mistake in questioning how tight these two are, or whether they have the other guy's back. When the Red Sox struggled in 2014 and it became clear Lester was getting traded out of Boston, Lackey no longer wanted to stay either. He felt Lester hadn't been dealt with properly during contract negotiations that spring and let management know, quietly, that without Lester, he would not pitch in Boston in '15 for the player minimum option of $500,000 -- plus performance incentives -- that had been negotiated in his contract.

As it turned out, both players were traded out of Boston on the same day -- July 31, 2014. Lackey went to St. Louis, while Lester went to Oakland before signing a six-year, $155 million contract with the Cubs this past offseason.

"I have nothing but respect for him," Lackey said. "I mean, me and him are going to be friends long after this thing's over, and he's my boy. [I] wish him nothing but the best, but I'm going to try to get after him tomorrow and I expect nothing but the same from him. I know he's going to be ready to go. It's going to be a challenge."

In a league-leading 33 starts this season, the 36-year-old Lackey was 13-10 with a 2.77 ERA over 218 innings. Lester, 31, got off to a slow start in Chicago but finished 11-12 with a 3.34 ERA in 32 starts and 205 innings.

"In '13 when I was playing with him, he was probably the best on the planet going through the playoffs that year," Lackey said. "It's just his preparation. He works hard. He's ready. I mean his stuff is obviously really good. But he knows how to compete and he knows how to handle this time of year for sure."

Lester expects Lackey to give him more of the same.

"He's just such a good competitor, you know," Lester said. "He's going to almost out-will you sometimes, if that makes sense. I learned a lot from him in Boston."

• Tale of the Tape: Lackey vs. Lester

Lackey and Lester have pitched against each other before -- including earlier this season on July 6. And they had a little fun with it, too.

Lester allowed two unearned runs over seven innings, but took a loss in a 6-0 defeat for the Cubs. Lackey spun seven scoreless innings that game. Lester did, however, come out on top against Lackey in the batter's box, collecting an infield single that deflected off one of the Cardinals starter's legs.

Video: Must C Clips: Lester tallies first MLB hit in 67th AB

That snapped an 0-for-66 slump that dated back to 2006 for Lester, who wound up with four hits (three against St. Louis) this season. When it was over, Lackey was asked if he would sign the ball for his buddy.

Said Lackey: "I'll autograph it. And I'll put, 'You lost,' too."

Lester and Lackey surely shared a few laughs over that moment later that night, too, as they met up and hung out at the Cardinals pitcher's house after the game.

"He's already one up on me this year, so hopefully I can get back to even tomorrow with him," Lester said.

Catcher David Ross was in Boston with both pitchers and signed with Chicago to join Lackey last winter.

"They're both big rednecks," Ross said. "I love 'em both, but we're going to try to kick one of their tails tomorrow. ... They're good guys. It's going to be fun tomorrow."

Lester was surprised when he learned that he drew a start against his friend.

"I thought it was funny. I mean, it's kind of fitting," Lester said. "Add a little bit more to it, but at the end of the day, I can't worry about who's going against me on the other side."