There is good news surrounding the injury recovery of Chicago Cubs left-handed starting pitcher Shota Imanaga.

The 31-year-old threw a 37-pitch bullpen session in Arizona on Saturday, per Marquee Sports’ Taylor McGregor. This comes after Imanaga threw a live batting practice earlier in the week.

In that batting practice session he threw 39 pitches, the equivalent of two innings.

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So, the lefty has now thrown the equivalent of four innings in four days. The next step comes on Monday in Arizona, per McGregor.

She reported that the Cubs intend for him to throw in a live game in Arizona. This would be with the Arizona Complex League Cubs, who are at the ACL Rockies.

McGregor didn’t report what is next for Imanaga. But pitching progressions during the injury recovery phase are typical. If he throws well on Monday and shows no setbacks the next day during recovery, the start of a rehab assignment at a full season affiliate is possible by week’s end.

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Imanaga went on the injured list on May 5 with a left hamstring strain. Given that he’s been on the 15-day injured list for a month, he’ll probably need a start or two in the minor leagues before he can be ready to be activated.

Through eight starts he was 3-2 with a 2.82 ERA, with 34 strikeouts and 14 walks in 44.2 innings. His health is paramount for the Cubs and their hopes beyond winning the National League Central Division. Their other left-handed standout, Justin Steele, is out for the season after elbow surgery.

Without him, Chicago has remained one of the best teams in the National League, bolstered by its offense. To augment the rotation, the Cubs called up top prospect Cade Horton, who has fit in nicely and has claimed three wins in his first five appearances going into Sunday’s game against Detroit.

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Jameson Taillon, Matthew Boyd, Ben Brown and Colin Rea make up the rest of the rotation right now.

With Imanaga’s injury and the relative lack of depth in the rotation, MLB insiders believe the Cubs will try and make some kind of move for a starting pitcher at the trade deadline at the end of July.

Hopefully Imanaga is back by then and his presence in the rotation gives Chicago leadership a better idea of what type of starter is needed for a stretch run that some believe could include the Cubs returning to the World Series.

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