During his sophomore season in 2009 he made 54 receptions for 1,080 yards and eight touchdowns in the regular season. including six catches for 113 yards and two touchdowns against Cincinnati in the final game with the conference championship on the line, but Pittsburgh lost by one point.
Heading into the 2010 season, Lindy's listed him as the nation's No. 3 wide receiver and a second team All-American while the Sporting News listed Baldwin as a third-team preseason All-American. In 2010, he had 55 receptions, 822 yard and five touchdowns in 13 games.
Baldwin was selected with the 26th overall pick in the 2011 NFL Draft by the Kansas City Chiefs. He was expected to be the 2nd WR on the roster behind Dwayne Bowe. On July 29, 2011 he signed a 4-year deal with the Chiefs. In week 2 of the 2011 NFL preseason Baldwin suffered a wrist injury after a locker room fight with teammate Thomas Jones that sidelined him for the rest of the 2011 preseason. Baldwin caught his first NFL catch against the Raiders on week 7 for 14 yards. On October 31, 2011 Baldwin played in his first game at Arrowhead Stadium as he played a key role in the Chiefs 23-20 victory over the San Diego Chargers. Baldwin caught 5 passes for 82 yards as well as catching his first career NFL touchdown on a 39 yard pass from Matt Cassel. Baldwin would finish the year with 254 receiving yards and one touchdown.
Baldwin has two sisters and is the son of Jeffrey and Tezmalita Baldwin. His father was a defensive lineman at Pitt from 1981–84. His cousin Charles Fisher played cornerback in the NFL for the Cincinnati Bengals.