Vincent Lopez (born January 22, 1949), nicknamed Mad Dog, is an American drummer. Between 1968 and 1974, he backed Bruce Springsteen in several bands, including Steel Mill and the E Street Band. He also played on Springsteen's first two albums, Greetings from Asbury Park, N.J. and The Wild, the Innocent and the E Street Shuffle. Both during and after his time with the E Street Band, Lopez played drums with numerous Jersey Shore bands.

In April 2014, Lopez was inducted by Springsteen into the Rock and Roll Hall of Fame as a member of the E Street Band.

Vincent Lopez grew up in Neptune Township, New Jersey where he attended Neptune High School with future E Street Band bass player Garry Tallent and Southside Johnny. From 1956 to 1962, he played the soprano valve bugle in a Drum and Bugle Corps. Then, as a teenager, he taught himself the drums and began playing with Buzzy Lubinsky, a drummer/DJ based in Asbury Park. Lubinsky's father was Herman Lubinsky, owner of Savoy Records in Newark. Lubinsky would subsequently act as a mentor for the young Lopez. Starting in 1964, with encouragement from Lubinsky, he began to try out for local bands. After a failed audition for the Storytellers, a band which included Bill Chinnock and future E Street Band keyboardist Danny Federici, he successfully auditioned for the Blazers, led by Sonny Kenn. They subsequently became Sonny & The Sounds and then Sonny & The Starfires.

After graduating from high school in 1967, he continued to play with several local bands. These included the Downtown Tangiers Band, with Federici, Chinnock and Garry Tallent, and Moment of Truth with Tallent, Tom Worieo, and Ricky DeSarno (guitar). DeSarno and Lopez would become regular collaborators after Lopez left the E Street Band. In 1970, Lopez worked at Carvers boatyard in Point Pleasant, New Jersey.

In 1968, The Upstage Club was opened at 702 Cookman Avenue in Asbury Park. The club would play a central role in the history of both Bruce Springsteen and the E Street Band and Southside Johnny & The Asbury Jukes. In February 1969, Springsteen and Lopez got together with Danny Federici and Vinnie Roslin at The Upstage and formed a new band. Vini got in touch with Carl “Tinker” West and he became the band's manager and mentor. They initially played as Child but in November 1969 changed their name to Steel Mill to avoid confusion with another band. Springsteen and Lopez had already met on several occasions. On April 22, 1966, they played with their respective bands, the Castiles and Sonny & The Starfires, in a battle of the bands competition at the Matawan-Keyport Roller Drome in Matawan, New Jersey.

During the early 1970s, Lopez and Springsteen would go on to play together in several short-lived bands based out of the Upstage. These included Bruce Springsteen & The Friendly Enemies, the Sundance Blues Band, Dr. Zoom & The Sonic Boom Band and the Bruce Springsteen Band. Most of these bands included a core membership of Danny Federici, Garry Tallent, David Sancious, Steve Van Zandt and Southside Johnny. The Bruce Springsteen Band also included Delores Holmes and Barbara Dinkins. Dinkins would later be replaced by Francine Daniels.

In 1972, after Springsteen signed a recording contract with Columbia Records, he returned to The Upstage to recruit a band to record and then tour in support of his upcoming debut album, Greetings from Asbury Park, N.J.. Together with Danny Federici, Garry Tallent, David Sancious and Clarence Clemons, Lopez was a founding member of what eventually became the E Street Band. It was also around this time that Clive Davis first gave Lopez his "Mad Dog" nickname. By 1973, they had recorded a second album with Springsteen, The Wild, the Innocent and the E Street Shuffle. Other recordings from this era featuring Lopez would later be released on the compilations Tracks and 18 Tracks. Lopez left the band in acrimonious circumstances. He got into a fight with Steve Appel, the band's road manager and brother of then manager Mike Appel, and was fired by Springsteen. In a 2005 interview with The New York Times, Lopez said, "At that point, I didn't think the band was going to go too far and I didn't care either... I made a few mistakes, you know, everybody makes mistakes. I still thought it was my band."

Since his departure from the E Street Band, Lopez has reunited with Springsteen on multiple occasions. On September 8, 1974 at The Stone Pony, following a set by the Blackberry Booze Band, Springsteen, accompanied by Lopez and Garry Tallent, joined Southside Johnny for several songs, including a rendition of "Twist and Shout". Shortly afterwards, the Blackberry Booze Band, led by Southside Johnny and Steve Van Zandt, became Southside Johnny & The Asbury Jukes.