George Kittle and Fred Warner both missed the 49ers practice on Wednesday

This is something that needs to be monitored.

George Kittle (ribs) and Fred Warner (ankle) both missed practice on Wednesday, meaning it's entirely possible one or both of them will miss Sunday's home game against the Arizona Cardinals.

Both Kittle and Warner suffered their injuries last Sunday during the 49ers' 30-13 victory over the New England Patriots. Kittle returned to the game and Warner did not. But at Wednesday's practice, Warner at least showed up, running 30-yard dashes at 75 percent speed on a side field. Kittle couldn't even do that much. So it appears Warner is more likely to play on Sunday than Kittle.

So far this season, Kittle has had to sit out at least a few plays in three of the 49ers' four games. In Week 2, he had to leave the game to receive an IV due to leg cramps. In Week 3, he was forced to miss the entire game due to a hamstring injury. And in week 4 he injured his rib. Since he's almost 31 years old, it's fair to wonder if he's starting to break down, as all athletes do at some point.

Meanwhile, Warner has only missed one game in his seven-year career. So if he can play physically on Sunday, I expect he will.

But he couldn't physically play against the Patriots in the second half. And when he ran sprints Wednesday alongside linebacker Dee Winters, who also has an ankle injury, Warner ran noticeably slower than Winters. Which suggests Warner's injury could be worse than Winters'.

Stay tuned.

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