There’s a cautionary tale in first baseman Brett Wallace, whose time with the Astros may be up after four seasons.

The team on Thursday designated the first baseman for assignment, giving the club 10 days to trade, release or outright Wallace to the minors. Wallace would have to pass through waivers for the Astros to be able to keep him in their system, meaning the 29 other teams would have to decline a chance to take him.

The Astros needed a space on their 40-man roster to make room for newly signed pitcher Jerome Williams, and Wallace became the odd man out.

“A lot of times players get caught up in number crunches,” Astros manager Bo Porter said Thursday. “We actually hope that we’re able to retain Brett Wallace. He was a valuable part of our team last year and with the hope of retaining him, there’s no doubt in my mind that he will be a valuable part of our team if we’re able to retain him. But when it comes down to the roster construction, as you sit here today, we have to make again the best decision for the Houston Astros today with a watchful eye on tomorrow.”

What might help keep Wallace in the Astros’ organization is the fact that Wallace is out of options. Therefore, if he hits waivers, an opposing team that want to claim him can’t immediately stash him with their Class AAA affiliate.

Wallace, 27, came to the Astros in 2010 in a trade with the Blue Jays that piggy-backed off the Roy Oswalt trade with the Phillies.

Oswalt was dealt to the Phillies for a package that included Anthony Gose, and Gose was sent to the Blue Jays in exchange for Wallace.

“Brett Wallace is a hitting machine,” Astros general manager Ed Wade was quoted as saying at the time.

Current Astros general manager Jeff Luhnow was the scouting director of the Cardinals in 2008, when the Cards took Wallace in the first round at No. 13 overall.

There have always been high hopes for Wallace. But as the Astros enter a season where several of their top prospects are expected to eventually arrive — including another strikeout heavy first baseman, Jonathan Singleton — Wallace stands as proof that they won’t all work out as envisioned. Not right away, at least.

Wallace hit a career-high 13 home runs last season but batted .221 in 79 games.

Only three other qualified first baseman struck out at a higher rate in the time Wallace has been in the majors, from 2010-13: Adam Dunn, Chris Davis and Mark Reynolds. Wallace has fanned nearly 30 percent of the time.

Lifetime, Wallace is a .242 hitter with a .313 on-base percentage, and as a left-handed hitter, he particularly struggles against southpaw pitching.

If the Astros can keep Wallace in the system, he’d be in competition to win playing time at first base, perhaps in a platoon with offseason addition Jesus Guzman. If he’s gone, that would leave catcher Jason Castro as the only remaining Astros player who played for the major league team in 2010.