Although serial verb constructions (SVCs) are widely observed across languages, there is ongoing debate regarding their syntactic representation, particularly in cases involving shared arguments. Two prominent approaches to SVCs with argument sharing are the double-headed structure proposed by Baker (1989) and the control structure suggested by Collins (1997). This paper presents novel data from Igbo to evaluate these differing approaches. First, we disentangle the confound between covert coordination and SVCs through syntactic and semantic tests, demonstrating that SVCs do exist in Igbo. We then conduct a comprehensive comparison between SVCs and corresponding verb-verb (V-V) compounds. The absence of a systematic derivational relationship between SVCs and V-V compounds raises doubts about the verb incorporation mechanism posited by Collins. Furthermore, the lack of resultative SVCs in Igbo challenges the existence of an empty category, further undermining the control structure for SVCs. In contrast, we illustrate that the endocentric property of Igbo SVCs aligns naturally with Baker's double-headed syntactic structure. Building on this, we propose a double-headed structure for SVCs in Igbo, both with and without shared arguments. Our findings thus provide a novel argument for a permissible structure of SVCs with argument sharing and for the availability of double-headedness in Universal Grammar.