Complex sentence: With Montana out, the Niner offense stalled, and the Giants won, 15--13, on the last of five Giants field goals, the last of which was set up by a fumble from 49ers running back Roger Craig.
Split into simpler sentences: With Montana out, the Niner offense stalled, and the Giants came back to win 15--13. The Goants kicked five field goals, the last of which was set up by a fumble by 49ers running back Roger Craig.