Joe Kelly left Wednesday's game against the Brewers with a left hamstring injury.
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Kelly was trying to beat out a bunt and grabbed at the hamstring after running through the bag. He had to be helped down the dugout steps, so the odds of him needing a disabled list stint are probably pretty good. Carlos Martinez would be the obvious choice to replace Kelly in the rotation, though it's possible the Cards will elect to leave him in the bullpen and promote someone like Tyler Lyons.
Rangers prospect RHP Luke Jackson fired six scoreless innings Tuesday for Double-A Frisco, allowing three hits and two walks while striking out eight batters.
Jackson, 22, was rocked for seven runs in 3 1/3 innings his last time out, so it was good to see him get back on track Tuesday. Overall, the right-hander owns a 4.40 ERA and 12/5 strikeout-to-walk ratio through 14 1/3 innings this season. Jackson is likely to contribute in the major leagues later this season if all goes as planned with his development.