SB 6.12.24

āvidhya parighaṁ vṛtraḥ
 kārṣṇāyasam arindamaḥ
indrāya prāhiṇod ghoraṁ
 vāma-hastena māriṣa
Word for word: 
āvidhya — whirling; parigham — the club; vṛtraḥ — Vṛtrāsura; kārṣṇa-ayasam — made of iron; arim-damaḥ — who was competent to subdue his enemy; indrāya — at Indra; prāhiṇot — threw; ghoram — very fearful; vāma-hastena — with his left hand; māriṣa — O best of kings, Mahārāja Parīkṣit.
Translation: 
O Mahārāja Parīkṣit, Vṛtrāsura, who was completely able to subdue his enemy, took his iron club, whirled it around, aimed it at Indra and then threw it at him with his left hand.