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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Emma Jesson brings you Sunday night's forecast
Wet and windy spells, interspersed with drier interludes this week. Wintry showers and variable temperatures. Gales and a weather warning
Wetter in the west, cloudy but direr further east. Milder than of late, but blustery