Jack Pennington-Jones has reached the quarterfinals of the ATP Tour at the Dallas Open

Britain’s Jack Pennington-Jones has reached his first ATP Tour quarter-final, continuing his impressive run at the Dallas Open.

The 22-year-old, who had to pass two qualifying rounds to reach the main draw of the tournament, followed up his stunning victory over Italian Flavio Coppoli, ranked 20th in the world, by defeating American Elliot Spizzeri to reach the quarter-finals.

Pennington Jones, ranked 181 in the world, defeated Spizzeri, ranked 68 in the world, in three sets, winning 7-6 (7-5), 4-6, 7-6 (7-4).

He will face former US Open champion Marin Cilic for a place in the semifinals on Friday.

Pennington Jones completed his junior season at Texas Christian University in May but chose not to return for his senior year in order to pursue a full-time tennis career.

After losing his first qualifying match at the Australian Open in January, Pennington-Jones reached the final at Soma Bay in Egypt before beginning a four-match winning streak in Dallas.

He is expected to rise 43 places to 138th in the world after reaching the quarter-finals, and he could enter the top 110 by defeating Cilic.

Elsewhere, Australian Open champion Elena Rybakina and top seed Iga Swiatek suffered two shock defeats at the Qatar Open.

Rybakina, ranked third in the world, lost to Canadian Victoria Mpoko 7-5, 4-6, 6-4, while Swiatek won the first set, but lost to Maria Sakkari 2-6, 6-4, 7-5.