Chicago Cubs attempted to trade for Detroit Tigers star Justin Verlander

July 4 (UPI) -- The Chicago Cubs recently tried to improve it's starting rotation ERA of 4.47 by asking about the availability of Detroit Tigers pitcher Justin Verlander.

Sources told MLB Network the Cubs inquired to the Tigers about the availability of Verlander and Alex Avila. Those sources added that neither side has engaged in trade negotiations.

Verlander, 34, has a 4.96 ERA in 17 starts this season, his worst mark since his rookie year in 2005. He has a 5-5 record with 92 strikeouts in 98 innings. Last season Verlander threw a league-high 254 strikeouts. The 2011 Cy Young Award winner and American League MVP owns a 3.53 career ERA and has 2,289 career strikeouts. The six-time All-Star has played his entire 13-year MLB career for the Tigers. Verlander was the No. 2 overall pick in the 2004 MLB June Amateur Draft.

Verlander allowed seven runs on nine hits in 3.1 innings Sunday in the Tigers' 11-8 loss to the Cleveland Indians at Comerica Park. The contest marked the first time in 331 games that Verlander didn't have a strikeout. His last game without a strikeout was in 2007.

Interested teams told ESPN that the "perception" is that the Tigers are looking for a big return without a salary offset. Verlander is due $28 million annually through 2019. He has a $22 million vesting option for 2020.

The Tigers (36-45) are currently in last place in the American League Central, while the Cubs (41-41) are in second place in the National League Central.

On Tuesday the Cubs traded catcher Miguel Montero to the Toronto Blue Jays in exchange for cash or a player to be named later.

Several front-office sources told Yahoo Sports last week they expect Verlander to hit the trade market sometime in early to mid-July.

Verlander's contract includes a no-trade clause. Three or four teams are interested in the Tigers star, according to FanRagSports. The Los Angeles Dodgers showed the most interest in Verlander this winter, according to the report.

The Cubs had a scout attending Sunday's contest, according to MLB Network. Major League Baseball's trade deadline in on July 31.