 The regiment was deployed for defense at Tienhaara, which was located along the coastal highway leading north from Viipuri towards the inner of Finland, on the shore of Kivisillansalmi on June 22 relieving the worn out troops.Having strong artillery support and support of the Gefechtsverband Kuhlmey the regiment was able to keep the Tienhaara region including the Kivisillansalmi while defending against repeated attacks by two Soviet divisions of the 108th Corps supported by strong artillery.At the conclusion of the battle on June 23 Marttinen was promoted to colonel.