Shrewsbury goalkeeper Chris Weale fouled JP McGovern in the area on 68 minutes and Miller put United back on terms.
The game ended 2-2 but there was worse news for Carlisle with winger Matty Robson limping out of the game after only nine minutes with a suspected back problem
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Kerrie Gosney brings you Saturday night's forecast
Severe gales possible for a time north of the border overnight. A cold, raw wind sets in Sunday. Showers turning wintry Monday & Tuesday.
Today, the Government announced plans to increase rail services in the North. But what does it mean for Cumbria?