he Cubs may decide they like relievers Hector Rondon and Justin Grimm, but not at the price they would have to pay them as arbitration-eligible players. After their subpar 2017 seasons, the Cubs may opt not to offer arbitration-eligible Hector Rondon and Justin Grimm contracts before Friday night’s deadline because the salary increases they still could receive under the raise-friendly arbitration system may make their arbitration cost prohibitive. Though Rondon and Grimm were effective in previous seasons and provide plenty of experience, the Cubs may continue to seek bullpen upgrades through trades and free agency. Pedro Strop and Carl Edwards Jr. are the club’s only other experienced right-handed relievers, with a combined 559 major-league appearances. The Cubs have added Matt Carasiti, Luke Farrell and Cory Mazzoni to the 40-man roster since the end of the season, but they have only a total of 43 big-league appearances. The Cubs are expected to announce the signing of free agent left-handed reliever Dario Alvarez, who posted a 2.76 ERA in 20 appearances for the Rangers last season. Alvarez, 28, struck out 17 but walked 14 in 16 1/3 innings with the Rangers and has pitched for the Mets, Braves and Rangers over parts of the last four seasons. Alvarez possessed better control at Triple-A Round Rock, where he walked 10 while striking out 36 in 27 innings in addition to a 2.33 ERA in 18 appearances. The Cubs appear covered from the left-side, with Mike Montgomery serving as a swingman and Justin Wilson expected to rebound from a rough two months after being acquired from the Tigers at the July trade deadline.