In spring training, there was denial.
"It's a non-issue for me," Cubs manager Joe Maddon said as the season began.
Then in April came slight acknowledgement after Lester threw wild to first base on his second attempt in nearly two years.
"From the outside looking in, I get it," Maddon said. "I know what everyone is talking about."
On Thursday came full-on acceptance -- or close to it -- after Lester threw wide of first base against the Milwaukee Brewers, who went on to steal five bases in the Cubs' 9-2 victory.
"We all know what's going on here," Lester said after the game.
What's going on is a mental block for one of the great pitchers of his era. Until perhaps last year's wild-card game, when the Kansas City Royals stole three bases on him, it never really was a problem for Lester in the American League. But it's become one with the Cubs, where Lester has given up a league-leading 35 stolen bases. To be fair, it's not so much an issue now as it could be in another playoff contest. Lester has pitched around his base-throwing issues.
"The bottom line is concentrating on the hitters," pitching coach Chris Bosio said Friday morning. "We practice things that are works in progress, but the bottom line is you have to get the hitters out."
So far the two-time World Series champion has done just that, becoming the first Cubs lefty to record 10 or more strikeouts in at least four starts in a season. He's 8-8 with a 3.21 ERA with a 1.18 WHIP. Both his ERA and WHIP are better than his career numbers. But there's that perplexing and unexplainable issue: He can't throw to first base. Two of three pick-off attempts this season have gone for errors. He's also not comfortable throwing to any base.
"We don't know why," catcher David Ross said. "If we knew why we would fix it."
If you think you have a suggestion for Lester on how to overcome the block, save it; the Cubs have heard and tried it.
"We've said it all," Bosio said. "There is nothing new anyone is going to suggest to us or to Jon. The bottom line is he keeps working on it."
Maybe it should be worrisome that Lester has been working on it since spring training and is still having problems. Maybe it takes baby steps, as he thought his throw on Thursday was better than the wild one he chucked in April against the Cincinnati Reds.
"It's a work in progress," Bosio said.
Can it be fixed or does it even need to be before a possible playoff game for the Cubs? The Brewers only scored one run off all that running plus the throwing error, but what if that run is the difference in the game?
"We all have things we have to work on," Ross said. "It's not rational. It's more mental than physical."
Back to the stages. After going through them all this season, Lester has landed at the final one: Self-deprecating humor. Maybe it will be the key to the whole mystery.