Todd Helton was placed on the disabled list on Friday because of a hip injury. (US Presswire)

When a baseball player is 38, any injury could be career-threatening, but a hip injury could be even worse. So, when the Rockies placed Todd Helton on the disabled list before Friday night's game, it's fair to wonder if we're seeing the last of the Colorado first baseman.

Helton, 38, was hitting just .235/.332/.398 -- all career-worst marks -- this season and well below his career marks of .320/.419/.545. He'd been slowed all season by the right hip and he'll have an MRI soon, according to the Denver Post.

"Because he was experiencing some soreness, we did shut him down for several days prior to trying it on Sunday -- it wasn't very good," Rockies manager Jim Tracy told reporters, including the Post. "He came in [Friday] and he's still sore. Now there needs to be some intervention … and we have to try to get to the very bottom of it."

It was a hip injury that ended Carlos Delgado's career, while Alex Rodriguez and Chase Utley haven't been the same since their hip injuries. Delgado last played in 2009, but didn't officially retire until last season -- at the age of 38.

Helton has one more year on the three-year extension he signed following the 2010 season. He's making $4.9 million this season and will make $5 million next season.

If he does retire, Helton will be an interesting candidate for the Hall of Fame in five years. So far voters have taken a skeptical view of Rockies hitters. Helton has 2,415 hits in his 16 seasons, to go with 354 home runs. A five-time All-Star, Helton has a batting title and three Gold Gloves under his belt.

Despite his numbers, he never finished higher than fifth in MVP voting. His home/away splits for his career were drastic -- in 4,586 plate appearances in Denver, he hit .350/.447/.614. In 4,398 plate appearances away from the altitude and spacious outfield of Coors Field, he hit .289/.389/.475. Of his home runs, 216 came at home, 138 away from home. No matter where he played, Helton was a fine hitter, but in the thin air, he was at another level. That'll be something for voters to consider when his time comes -- and that time seems to be coming closer every day.

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