Question: Steven Levert "Steve" Clarkson (born October 31, 1961) is an American football coach, Clarkson has tutored Matthew Montgomery Barkley, an American football quarterback who is currently a free agent, born on which date?

Context paragraphs:
Matt McGloin: Matthew James McGloin (born December 2, 1989) is an American football quarterback who is currently a free agent.  He was the starting quarterback for the Penn State Nittany Lions football team from 2010 to 2012.  He is the first walk-on quarterback to start at Penn State since scholarships were reinstated in 1949.  Prior to his college career, McGloin was a Pennsylvania all-state quarterback while attending West Scranton High School.

Matt Simms (American football): Matthew Phillip Simms (born September 27, 1988) is an American football quarterback who is currently a free agent.  He played college football at Tennessee, before being signed by the New York Jets as an undrafted free agent in 2012.

Seth Doege: Seth Colton Doege (born December 18, 1988) is an American football coach and formerly professional Canadian football quarterback.  After playing college football for Texas Tech University, he was signed by the Atlanta Falcons as an undrafted free agent in 2013.  On February 27, 2014, he was signed to the Saskatchewan Roughriders of the Canadian Football League.  Doege was Texas Tech's starting quarterback for the 2011 and 2012 seasons.  He is currently the wide receivers coach for Bowling Green.

Keith Price: Keith Price (born June 28, 1991) is an American football quarterback who is currently a free agent.  He played college football at Washington, where he was the starting quarterback from 2011 to 2013.  He was signed as an undrafted free agent by the Seattle Seahawks in 2014.  He has also played professionally in the Canadian Football League (CFL), where he was a member of the Saskatchewan Roughriders and the BC Lions.

Steve Clarkson: Steven Levert "Steve" Clarkson (born October 31, 1961) is an American football coach.  Based in Pasadena, California, he is considered a top quarterback coach.  Clarkson has tutored Ben Roethlisberger, Brett Hundley, Matt Leinart, J. P. Losman, Gino Torretta, Matt Barkley, Tim Tebow, Josh Freeman, and Jimmy Clausen, among others.  Clarkson is also known for helping to get offers for David Sills from University of Southern California and Tate Martell from the University of Washington at ages of 13.  David Sills currently attends West Virginia University and Tate Martell has committed to Ohio State University.

Anthony Jennings: Anthony Jennings (born October 31, 1994) is an American football quarterback who is currently a free agent.  He played college football for the LSU Tigers from 2013 to 2015 and the Louisiana-Lafayette Ragin' Cajuns in 2016.

Matt Barkley: Matthew Montgomery Barkley (born September 8, 1990) is an American football quarterback who is currently a free agent.  He played college football at USC, and was drafted by the Philadelphia Eagles in the fourth round of the 2013 NFL Draft.  Barkley has also played for the Arizona Cardinals, Chicago Bears and San Francisco 49ers.

Taylor Potts: Taylor Potts (born October 13, 1987) is a former American football quarterback.  He played college football at Texas Tech, and was signed by the St. Louis Rams as an undrafted free agent in 2011.  He was waived during training camp, and then signed as a free agent by the San Diego Chargers in May 2012, where he was expected to compete for the third-string quarterback position.

Alex Carder: Alex Carder (born October 22, 1989) is an American football quarterback who is currently a free agent.  He was signed as a free agent by the Detroit Lions of the National Football League.  He was formerly the starting quarterback at Western Michigan University.

Graham Harrell: Graham Stanton Harrell (born May 22, 1985) is an American Football assistant coach and former American football and Canadian football quarterback.  He is currently the offensive coordinator and quarterbacks coach for the North Texas Mean Green.  He had been an assistant for the Washington State Cougars for the previous two seasons and had also worked for Oklahoma State in a quality control position .  He played college football at Texas Tech University, where he was an All-American quarterback, Heisman Trophy finalist in 2008, and set school, conference and national records for passing yards, attempts, completions, and touchdown passes.  Harrell was signed into the National Football League in 2010 by the Green Bay Packers.  He was a part of the Super Bowl XLV win with the Packers over the Pittsburgh Steelers.  He was also a member the New York Jets.  Prior to his time in the NFL, he was signed by the Saskatchewan Roughriders in 2009 as an undrafted free agent in the Canadian Football League.

Supporting paragraphs: Steve Clarkson Matt Barkley
Answer: September 8, 1990