He played in Major League Baseball (MLB) for the Atlanta Braves, St. Louis Cardinals, Chicago Cubs, Colorado Rockies, Washington Nationals, Arizona Diamondbacks, San Diego Padres, Minnesota Twins, and Cincinnati Reds.

Marquis was drafted in the first round out of high school by the world champion Atlanta Braves, and reached the majors as a 21-year-old in 2000.

[4] Marquis was born in Manhasset, New York, and grew up in Staten Island's Arden Heights neighborhood, where he attended Paulo Intermediate School 75.

[1] His mother works for the New York City Board of Education, and has a teaching degree, while his father owns a check cashing business in Brooklyn.

[11] Through 2014, he was third all-time in career wins and strikeouts (behind Ken Holtzman and Sandy Koufax in both categories) among Jewish major league baseball players.

[14] His team lost to California in the US final on ESPN, as Marquis was relegated to shortstop because Little Leaguers weren't allowed to pitch two days in a row.

"[17] As a 6 ft 1 in (1.85 m) junior and senior, however, Marquis threw a 93 miles per hour fastball, a curveball that was nearly unhittable at the high school level, and a changeup.

The first was a Pirates (22–1) championship in 1995 over the George Washington Trojans (32–3), 3–2 at Shea Stadium, capping a season in which he posted an 11–0 record while striking out 86 batters in 61 innings.

He pitched his team to a 5–1, 7-inning complete game victory in which he struck out 15 batters and did not allow any earned runs, while he himself hit a two-run triple, at Yankee Stadium.

[21] Anthony McCarron of The New York Daily News touted him as "perhaps the city's best high school player since ... Manny Ramirez," and Baseball America ranked him the 39th-highest prospect in the nation.

[23][27] In 1996 Marquis began his pro career with the Danville Braves (Rookie Advanced) in the Appalachian League, going 1–1 with a 4.63 ERA in 7 games.

[24] Marquis was named Baseball America Carolina League Player of the Week for the period April 15–21, as he pitched 10.0 innings, striking out 11.

He spent much of the summer on the disabled list (DL) with a sore elbow, a tender right shoulder, and a pulled oblique stomach muscle.

The 9/11 attack that interrupted the season also led to the death of one of his Little League World Series teammates, Michael Cammarata, a firefighter.

In 2003, the Braves revamped their starting rotation with the acquisitions of Mike Hampton, Russ Ortiz, Shane Reynolds, and the promotion of Horacio Ramírez from AA.

On December 13, 2003, Marquis was traded to the St. Louis Cardinals along with relief pitcher Ray King and rookie prospect Adam Wainwright for outfielder J. D. Drew and catcher Eli Marrero.

[36][37][38] Marquis strung together a Cardinals' season-high 11-game winning streak from May 31–September 4, the longest by a Cards pitcher since 1985 when John Tudor also won 11 straight games.

[7][37] He was bested, however, by Boston pitcher Derek Lowe, who threw shutout ball for seven innings to win the series for the Red Sox.

[7] With the Cubs, he wore his favorite # 21, the number formerly worn by ex-Cubs slugger Sammy Sosa, who coincidentally hit his 600th home run against Marquis.

He had a perfect game going into the 6th inning, retiring the first 16 batters he faced, but Pirates shortstop Don Kelly broke it up with a single.

[55] He made one appearance against the Dodgers in Game 1 of the National League Division Series, when he pitched the top of the ninth inning.

A reporter for MLB.com called it "one of the best pitching performances in Rockies history," and Rob Neyer of ESPN described Marquis that night as "Bob Gibson, Orel Hershiser, and Greg Maddux all rolled into one".

[70] He became the third pitcher in club history to win 11 games before the All Star break, the team record, joining Shawn Chacón (2003) and Aaron Cook (2008).

[77] Marquis is one of only six major league pitchers who won at least 11 games in each year from 2004 to 2009,[78] the others being CC Sabathia, Derek Lowe, Johan Santana, Javier Vázquez, and John Lackey.

[84] Marquis had 3 starts early in the 2010 season for the Nationals, posting an 0–3 record with a 20.52 ERA before being placed on the 15-day DL on April 22, 2010, with bone chips in his right elbow.

Marquis recorded his 1,000th career major league strikeout on June 18 against Ian Kinsler of the Texas Rangers in the second inning of an interleague game at Petco Park.

In July he suffered a complete tear of his ulnar collateral ligament in his right elbow and had Tommy John surgery, which ended his season.

When there was talk in the off-season about an Israeli team being fielded in the World Baseball Classic, Marquis said if it came about he would definitely be interested in playing to represent his heritage.

[7] In September 2012, Marquis was unable to pitch for Israel at the 2013 World Baseball Classic qualifier due to being active on a major league team.

[105] During the opening game of the qualifiers Marquis started and threw 41 pitches over three innings, while giving up two hits and one earned run, while recording a strikeout and a walk.