By Jonny Singer Follow @@Jonny_Singer Liverpool's new centre-back Dejan Lovren took to Twitter to celebrate marking his Liverpool debut with a headed goal. Lovren, who joined the Anfield club for £20million from Southampton this summer, was on target in the 13th minute, heading home a Steven Gerrard corner. And the Croatian, Liverpool's most expensive ever defender, put in a commanding display at the back as Brendan Rodgers' side recorded a thumping win over Borussia Dortmund. Joy: Lovren posts on Twitter acknowledging his superb debut against Borussia Dortmund Head start: The centre-back heads in Liverpool's second goal in just the 13th minute from a Gerrard corner
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Lovren scores Liverpool's second goal in 4-0 win
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Centre-back performs well on Anfield debut
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Liverpool finish pre-season on a high ahead of Premier League kick-off next Sunday
Thanks: Lovren applauds the Anfield crowd at the end of the final pre-season friendly for @placeholder' team