|Date of birth||7 May 1989|
|Place of birth||Lodi, Italy|
|Height||1.83 m (6 ft 0 in)|
|2009–2010||→ Frosinone (loan)||25||(0)|
* Senior club appearances and goals counted for the domestic league only and correct as of 30 July 2013.
During the season 2006–2007, Bolzoni was part of the winning side, when the reserve won the Campionato Nazionale Primavera (under-20 Italian Championship).
On 19 September 2007, Bolzoni, alongside with Esposito and Puccio, was selected for the first time in the 20-men squad for the 2006–07 UEFA Champions League match against Fenerbahçe. However he failed to make his debut in the UEFA Champions League, on that day. In the following match against PSV Eindhoven he came on as a substitute for Santiago Solari in the 70th minute, making his first UEFA Champions League appearance.
On 12 December, during an away match against PSV Eindhoven, Bolzoni started his first UEFA Champions League match, and also played the whole 90 minutes. The game ended in 1–0 win for Internazionale.
Bolzoni renewed his contract with the club until 30 June 2012 in 2008.
On 8 July 2010 Siena bought Bolzoni on loan for €400,000 with the possibility to acquire 50% of his ecnomic rights, fact that occurred on 22 June 2011, for €1,050,000. On 23 June 2012 Siena bought him outright for another €425,000.
- Inter Youth team Campionato Nazionale Primavera (Under-20 Italian Championship)
- Winner : 2006/07
- Runner-up : 2007/08
- Torneo di Viareggio
- Winner : 2008
- "Bolzoni extends Inter stay". www.inter.it. 15 July 2008.
- "PSV Eindhoven vs. F.C. Internazionale Match Report". www.inter.it. 12 December 2007.
- Genoa CFC Report and Accounts on 31 December 2009 (Italian)
- "L'UNDER 21 BOLZONI VA AL FROSINONE". www.genoacfc.it (in Italian). 17 August 2009.
- Genoa CFC Report and Accounts on 31 December 2010 (Italian)
- AC Siena Report and Accounts on 30 June 2011 (Italian)
- "Bolzoni in prestito al Siena". www.tuttomercatoweb.com (in Italian). 7 August 2010.
- "Bolzoni resta all'A.C.Siena Riscattata la metà del cartellino". www.acsiena.it (in Italian). 22 June 2011.
- AC Siena SpA Report and Accounts on 30 June 2012 (Italian)
- "Bolzoni ha lasciato il ritiro" (in Italian). AC Siena. 31 July 2013. Retrieved 1 September 2013.
- "Italy U21 call-ups for Alfonso, Bolzoni". www.inter.it. 5 October 2007.