The Annals of the Four Masters date the Battle of Clontarf to Easter Monday 1013, not 1014, so if we accept it was actually 1014, then for what happened in 1013, we examine what the AFM says for 1012:
M1012.8
Great forces were led by Maelseachlainn into the territory of the foreigners, and he burned the country as far as Edar; but Sitric and Maelmordha overtook one of his preying parties, and slew two hundred of them, together with Flann, son of Maelseachlainn; the son of Lorcan, son of Echthigern, lord of Cinel-Meachair; and numbers of others. This was the defeat of Draighnen; in commemoration of which this quatrain was composed:
1. Not well on Monday on the expedition did the Meathmen go to overrun;
The foreigners, it was heard, were joyful of the journey at the Draighnen.
http://www.ucc.ie/celt/published/T100005B/index.html