In the 2010 summer, still owned by the Che, Fausto joined CD La Muela also in the third level, starting in all of his league appearances but suffering team relegation. On 27 August 2011, he rescinded with Valencia and signed with UD Melilla in the same category;[2] he scored his first goal as a senior on 6 May 2012, against AD Ceuta.
On 15 August 2014, Fausto signed a one-year deal with Segunda División club AD Alcorcón.[5] He scored his first professional goal on 26 October, but in a 1–3 home loss against Real Zaragoza.[6]
On 1 July 2016, Fausto signed a two-year deal with CA Osasuna, newly promoted to the main category.[7] On 24 January 2018, he signed an 18-month contract with Cádiz CF in the second division, after cutting ties with his previous club.[8]
On 9 July 2018, Fausto terminated his contract with Cádiz,[9] and signed for fellow league team Extremadura UD eight days later.[10]
On 12 September 2019, Fausto signed a two-year contract with Greek club Panathinaikos for an undisclosed fee.[11] On the January transfer window, Fausto Tienza has officially returned to his native country. The 30-year-old has been heavily out of favour ever since joining the club only a few months ago. He only featured a mere 52 minutes for the club and has joined Gimnàstic de Tarragona in the Spanish third tier in a loan move until the end of this season.